CECO ENVIRONMENTAL CORP — Director's Dealing 2011

May 31, 2011

SEC Form 5 — Annual Statement of Changes in Beneficial Ownership

Issuer: CECO ENVIRONMENTAL CORP (CECE)
CIK: 0000003197
Period of Report: 2010-12-31

Reporting Person: DEZWIREK PHILLIP (Director, Chairman, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-09-01	Common Stock	P	1500	$5.82	Acquired	592212	Direct
2010-09-02	Common Stock	P	500	$5.80	Acquired	592712	Direct
2010-09-08	Common Stock	P	7500	$5.57	Acquired	600212	Direct
2010-09-09	Common Stock	P	1600	$5.71	Acquired	601812	Direct
2010-09-13	Common Stock	P	2800	$5.73	Acquired	604612	Direct
2010-09-14	Common Stock	P	2000	$5.82	Acquired	606612	Direct
2010-09-15	Common Stock	P	200	$5.76	Acquired	606812	Direct
2010-09-16	Common Stock	P	2600	$5.69	Acquired	609412	Direct
2010-09-23	Common Stock	P	1500	$5.96	Acquired	610912	Direct
2010-09-28	Common Stock	P	4000	$5.92	Acquired	614912	Direct
2010-09-29	Common Stock	P	600	$5.94	Acquired	615512	Direct
2010-09-30	Common Stock	P	2500	$5.94	Acquired	618012	Direct
2010-10-01	Common Stock	P	300	$5.95	Acquired	618312	Direct
2010-10-04	Common Stock	P	6700	$5.86	Acquired	625012	Direct
2010-10-05	Common Stock	P	4000	$5.96	Acquired	629012	Direct
2010-10-06	Common Stock	P	2800	$6.02	Acquired	631812	Direct
2010-10-07	Common Stock	P	1000	$6.27	Acquired	632812	Direct
2010-11-15	Common Stock	P	99	$5.49	Acquired	632911	Direct
2010-11-16	Common Stock	P	1500	$5.32	Acquired	634411	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	4700	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Warrant (right to buy)	$9.07	2016-12-28	Common Stock (250000)	250000	Indirect
6% Convertible Debenture (right to buy)	$4.00	2014-11-26	Common Stock (550000)	550000	Indirect

Footnotes

F1: 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. 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 purchased at each separate price within the ranges set forth in footnotes 1 through 16 in this Form 5.

F2: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.54 to $5.70, inclusive

F3: 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 $5.71, inclusive

F4: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.55 to $5.77, inclusive.

F5: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.79 to $5.84, inclusive.

F6: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.65 to $5.87, inclusive.

F7: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.57 to $5.76, inclusive.

F8: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.95 to $5.96, inclusive.

F9: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.88 to $5.98, inclusive.

F10: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.94 to $5.95, inclusive.

F11: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.79 to $5.99, inclusive.

F12: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.90 to $5.98, inclusive.

F13: 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 $6.00, inclusive.

F14: 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 $6.00, inclusive.

F15: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.94 to $6.08, inclusive.

F16: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.29 to $5.34, inclusive.

F17: Filer is President of Icarus Investment Corp. and disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein.