The drinks firm used a picture of Botham during his historic 1981 Test series performance against Australia in a print advertising campaign.
Botham's lawyer, Naynesh Desai, said Botham did not endorse the drink, nor did the firm seek the player's permission.
"He is contemplating legal action," said Desai, who claims Botham - now a television pundit - 'lost income' because of the advert.
Guinness confirmed it was holding talks with Botham's representatives, but that no legal action has yet been taken.
