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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
KOSKI ROBERT E
  2. Issuer Name and Ticker or Trading Symbol
SUN HYDRAULICS CORP [SNHY]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
1500 WEST UNIVERSITY PARKWAY
3. Date of Earliest Transaction (Month/Day/Year)
05/27/2005
(Street)

SARASOTA, FL 34243
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ 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 Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 05/27/2005   S   56,742 D $ 35 2,201,801 D (1)  
Common Stock               64,692 D (2)  
Common Stock               100,000 D (3)  
Common Stock               141,215 D (4)  
Common Stock               173 I (5) BY ESOP TRUST

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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 Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
KOSKI ROBERT E
1500 WEST UNIVERSITY PARKWAY
SARASOTA, FL 34243
  X   X    
KOSKI BEVERLY

 
    X    
KOSKI FAMILY LP

 
    X    
KOSKI CHRISTINE L

 
  X   X    
KOSKI ROBERT C

 
    X    
KOSKI THOMAS L

 
    X    

Signatures

 Gregory C. Yadley, as Attorney-in-Fact for ROBERT E. KOSKI, BEVERLY KOSKI, KOSKI FAMILY LIMITED PARTNERSHIP, CHRISTINE L. KOSKI, ROBERT C. KOSKI AND THOMAS L. KOSKI   06/01/2005
**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) Shares owned directly by Koski Family Limited Partnership. Shares owned indirectly by Robert E. Koski, Beverly Koski, Christine L. Koski, Robert C. Koski and Thomas L. Koski, each of whom is a general partner of the partnership or the controlling person of a corporate general partner of the partnership.
(2) Shares owned directly and solely by Christine L. Koski.
(3) Shares owned directly by Robert E. Koski and indirectly by Beverly Koski, Robert E. Koskis spouse.
(4) Shares owned directly by Beverly Koski and indirectly by Robert E. Koski, Beverly Koskis spouse.
(5) Reflects allocations of shares to Robert E. Koski under the Sun Hydraulics Corporation Employee Stock Ownership Plan.

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