The actress recently wrote a letter to the network asking them to show the important video.
She said: 'Although I played an ambitious dog trainer in Best in Show, in real life I wouldn't go near the Westminster Dog Show because it promotes the breeding of animals even as millions are dying for homes in shelters.'
The new public service announcement shows people playing and walking with their dogs that are in body bags.
Lynch said the ad for People for the Ethical Treatment of Animals represents the 'more than 4 million animals who must be euthanised each year because of a lack of good homes'.