Ownership Submission
FORM 5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Form 3 Holdings Reported
Form 4 Transactions Reported
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

ANNUAL STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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1. Name and Address of Reporting Person *
DEZWIREK PHILLIP
 2. Issuer Name and Ticker or Trading Symbol
CECO ENVIRONMENTAL CORP [CECE] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chairman
(Last)
(First)
(Middle)

2300 YONGE STREET, SUITE 1710		 3. Statement for Issuer's Fiscal Year Ended (Month/Day/Year)
12/31/2010
(Street)


TORONTO, A6 M4P 1E4		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Reporting
(check applicable line)

_X_ Form Filed by One Reporting Person
___ Form Filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned at end of Issuer's Fiscal Year
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Amount (A) or (D) Price
Common Stock 09/16/2008   P4 1,100 A $ 4.5 (1) 435,915 D  
Common Stock 09/23/2008   P4 4,000 A $ 4.51 (2) 439,915 D  
Common Stock 09/24/2008   P4 4,900 A $ 4.5 (3) 444,815 D  
Common Stock 09/26/2008   P4 13,657 A $ 4.14 (4) 458,472 D  
Common Stock 09/29/2008   P4 12,767 A $ 3.88 (5) 471,239 D  
Common Stock 09/30/2008   P4 38,070 A $ 3.83 (6) 509,309 D  
Common Stock 10/01/2008   P4 2,000 A $ 4.03 (7) 511,309 D  
Common Stock 10/02/2008   P4 500 A $ 4.14 511,809 D  
Common Stock 11/21/2008   P4 15,000 A $ 1.95 (8) 526,809 D  
Common Stock 12/09/2008   P4 5,000 A $ 2.47 (9) 531,809 D  
Common Stock 12/19/2008   P4 100 A $ 2.57 531,909 D  
Common Stock 01/15/2009   P4 2,500 A $ 2.58 534,409 D  
Common Stock 05/11/2009   P4 2,000 A $ 3.93 (10) 536,409 D  
Common Stock 05/29/2009   P4 6,000 A $ 3.32 (11) 542,409 D  
Common Stock 05/29/2009   S4 4,000 D $ 3.52 (12) (13) 538,409 D  
Common Stock 06/03/2009   S4 5,000 D $ 3.4 (13) 533,409 D  
Common Stock 06/04/2009   S4 2,500 D $ 3.58 (13) 530,909 D  
Common Stock 03/29/2010   P4 10,095 A $ 3.49 (14) 571,004 D  
Common Stock 04/08/2010   P4 3,996 A $ 3.73 (15) 575,000 D  
Common Stock 05/17/2010   P4 9,878 A $ 4.74 (16) 584,878 D  
Common Stock 06/11/2010   P4 500 A $ 4.6 585,378 D  
Common Stock 06/14/2010   P4 434 A $ 4.83 585,812 D  
Common Stock 06/15/2010   P4 1,000 A $ 5 (17) 586,812 D  
Common Stock 06/16/2010   P4 1,100 A $ 5.03 (18) 587,912 D  
Common Stock 08/18/2010   P4 1,000 A $ 5.85 (19) 588,912 D  
Common Stock 08/23/2010   P4 600 A $ 5.83 (20) 589,512 D  
Common Stock 08/25/2010   P4 500 A $ 5.63 590,012 D  
Common Stock 08/27/2010   P4 500 A $ 5.88 (21) 590,512 D  
Common Stock 08/30/2010   P4 200 A $ 5.81 (22) 590,712 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 2270 (9-02)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned at End of Issuer's Fiscal Year
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
(A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
DEZWIREK PHILLIP
2300 YONGE STREET, SUITE 1710
TORONTO, A6 M4P 1E4		   X   X   Chairman  

Signatures

/s/ Phillip DeZwirek 05/31/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The price reported in column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.48 to $4.53, inclusive. The reporting person undertakes to provide to CECO Environmental Corp., any security holder of CECO Environmental Corp., or the staff of the Securities Exchange Commission, upon request, full information regarding the number of shares sold or purchased, as applicable, at each separate price within the ranges set forth in footnotes 1 through 12 and footnotes 14 through 22 in this Form 5.
(2) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.50 to $4.55, inclusive.
(3) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.35 to $4.75, inclusive.
(4) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.08 to $4.18, inclusive.
(5) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.75 to $3.90, inclusive.
(6) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.72 to $3.98, inclusive.
(7) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.97 to $4.07, inclusive.
(8) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $1.79 to $2.00, inclusive.
(9) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $2.45 to $2.53, inclusive.
(10) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.91 to $3.94, inclusive.
(11) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.30 to 3.41, inclusive.
(12) The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $3.45 to $3.59, inclusive.
(13) In connection with this transaction, filer has voluntarily remitted appropriate profits to CECO Environmental Corp., pursuant to Section 16(b) of the Securities Exchange Act of 1934.
(14) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.41 to $3.55, inclusive.
(15) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.50 to $4.30, inclusive.
(16) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.65 to $4.85, inclusive.
(17) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.00 to $5.01, inclusive.
(18) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.98 to $5.03, inclusive.
(19) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.82 to $5.89, inclusive.
(20) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.70 to $5.86, inclusive.
(21) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.87 to $5.88, inclusive.
(22) The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.80 to $5.83, inclusive.
 
Remarks:
7 of 8

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