The accolade, which came at the inaugural RSPCA Alternative Awards, is the first formal recognition for the company since it began a period of sustained investment in its corporate social responsibility strategy.
A McDonald's spokeswoman declined to comment on any plans it had to highlight the achievement, but it is unlikely to flag it up in advertising for fear of sparking a backlash.
Other high-street winners at the awards included Waitrose and The Body Shop.
McDonald's has had to work hard to rebuild its image following the PR disaster of the 1997 "McLibel" trial when it successfully sued two environmental activists.
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