SecProbe.io

May 31, 2011

Mr. Julian Heslop
Chief Financial Officer
GlaxoSmithKline plc
980 Great West Road
Brentford, TW8 9GS
England

Re: GlaxoSmithKline plc
  Form 20- F for Fis cal Year Ended December 31, 2010
  File No. 001 -15170

Dear  Mr. Heslop:
 We have limited our review of your filing to those issues we have addressed in our
comments .   In our comments, we ask you to provide us with information so we may better
understand your disclosure.
 Please respond to this letter within ten business days by  providing the requested
information or by advising us when you will provide the requested response.  If you do not
believe a comment applies to your facts and circumstances, pleas e tell us why in your response.
Please furnish us a letter on EDGAR under the form type label CORRESP that keys your responses to our comments.
 After reviewing the information provided, we may raise additional comments and/or
request that you amend your filing.

Financial Review 2010
1. You refer to Note 3 to the financial statements for additional information on the judgments and estimates , associated with all  of your critical accounting policies other than turnover.
However,  Note 3 does not describe the key assumptions, underlying these six other  critical
accounting estimates, and only provides a sensitivity analysis for the discount rate, used to determine  the cost of providing pensions and other post -employment benefits. Please
provide us proposed disclosure to be included in future periodic filings to address your  other
critical accounting policies .  Critical accounting policies, page 40

Mr. Julian Heslop
GlaxoSmithKline plc.
May 31, 2011
Page 2

 Notes to the financial statements
2. Please provide us proposed disclos ure to be included in future periodic filings  showing a
disaggregation of the £4.111 billion charge for 2010 and the £2.047 billion amount paid in
2010 for each matter discussed on page 149, as the nature of these matters  does not appear
to be suffi ciently similar to warrant aggregation under  paragraph 87 of IAS 37. Also,
include in the proposed disclos ure the number of court cases that were settled by th ese
payments in 2010 and the number of court cases still open at December 31, 2010 and  tell us
your consideration of the disclosure guidance in SAB Topic 5Y Question 3 .  In addition,
include in the proposed disclos ure the factors that determined your recognition of the £4.111
billion legal charge obligation in 2010 instead of earlier periods .  29 Other provisions, page 148
3. You do not appear to have provided all of the disclosure described in paragraphs 84- 85 of
IAS 37 . Please provide us proposed disclosure to be included in future filings or explain to
us your basis for omitting this information.

 44 Legal proceedings, page 178
4. You indicate that the Group is involved in certain legal proceedings, where it is not possible
to make a reliable estimate of the expected future financial effect.  For legal proceed ings
where the possibility of an  outflow  in settlement is other than remote, please provide  us
proposed disclosure  to be included in future periodic filings  showing, for each class of
contingent liability, the disclosures  described in paragraphs 86- 92 of IAS 37, such as a
description of the nature of the  contingent liability and an estimate of the related reasonably
likely financial effect.

We urge all persons who are responsible for the accuracy and adequacy of the disclosure
in the filing to be certain that the filing includes the  information the Securities Exchange Act of
1934 and all applicable Exchange Act rules require.  Since the company  and its management are
in possession of all facts relating to a company’s disclosure, they are r esponsible for the accuracy
and adequacy of the disclosures they have made.

 In responding to our comments, please provide  a written statement from the comp any
acknowledging that:

• the company is responsible for the adequacy and accuracy of the disclosure in the filing;
• staff comments or changes to disclosure in response to staff comments do not foreclose
the Commission from taking any action with respect to the filing; and
• the company may not assert staff comments as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.

Mr. Julian Heslop
GlaxoSmithKline plc.
May 31, 2011
Page 3

You may contact Frank Wyman, Staff Accountant , at (202) 551- 3660, or Lisa Vanjoske,
Assistant Chief Accountant, at (202) 551- 3614, if you have questions regarding the comments.
In this regard, do not hesitate to contact me, at (202) 551- 3679.

Sincerely,

Jim B. Rosenberg
Senior Assistant Chief Accountant