Two years ago, Baldwin narrated a short documentary, "Meet Your Meat," for the People for the Ethical Treatment of Animals that helped lead to policy changes at Burger King, PETA (search) said.
The animal rights group said the video helped persuade Burger King (search) to sever its ties to slaughterhouses that fail unannounced audits and to lend support to the Humane Slaughter Act.
The company is now working with PETA to promote its veggie burgers nationwide, PETA said in a statement Monday to The Associated Press.
At the time, Baldwin said the video "makes the case for Americans to adopt a vegetarian diet and enact humane legislation to weed out the worst abuses."
Pamela Anderson and Chrissie Hynde of the Pretenders are previous recipients of the award. McCartney, a dedicated vegetarian, died of breast cancer in 1998.
Anderson, the Rev. Al Sharpton, Dennis Rodman, Andy Dick and Heather Mills McCartney are among those expected to attend the event, hosted by actor-comedian Fred Willard at the Paramount Pictures Studios.
Baldwin, 47, stars in the upcoming films "Elizabethtown" and "Fun With Dick and Jane."