Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF 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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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Desrochers Mark R
 2. Date of Event Requiring Statement (Month/Day/Year)
12/22/2009		 3. Issuer Name and Ticker or Trading Symbol
HANOVER INSURANCE GROUP, INC. [THG]
(Last)
(First)
(Middle)
C/O THE HANOVER INSURANCE GROUP, INC., 440 LINCOLN STREET		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Vice President
 5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

WORCESTER, MA 01653		 6. Individual or Joint/Group Filing(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 Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 10,053 (1)
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Common Stock (right to buy)   (2) 02/23/2017 Common Stock 3,610 $ 48.46 D  
Common Stock (right to buy)   (3) 02/23/2019 Common Stock 5,000 $ 34.19 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Desrochers Mark R
C/O THE HANOVER INSURANCE GROUP, INC.
440 LINCOLN STREET
WORCESTER, MA 01653		       Vice President  

Signatures

Mark R. Desrochers 12/23/2009
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(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) Includes (a) 1,026 restricted stock units that vest on February 23, 2010; (b) 2,750 restricted stock units that vest on February 25, 2011; (c) 535 restricted stock units that vest on March 7, 2011; (d) 2,255 restricted stock units that vest on August 1, 2011; (e) 1,000 restricted stock units that vest on February 23, 2012; and (f) 1,000 restricted stock units that vest on February 23, 2013. In each case the Reporting Person must be continuously employed by the Issuer through the applicable vesting date for such restricted stock units to vest. Upon vesting, such restricted stock units automatically convert into an equivalent number of shares of Common Stock.
(2) Such options vest 25% on February 23, 2008, 25% on February 23, 2009, and 50% on February 23, 2010.
(3) Such options vest 50% on February 23, 2012 and 50% on February 23, 2013.

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