Eww that is gross....

I think all dogs have wet dream that is the reason they are dogs because they are perveted and so forth so I would say yes.....

But if you are refering to cainines dogs don't because usally the reason for 'wet dreams' is because men tend to dream about dirty things there fore causing an erection and...the out come. So in less the dog is dreaming of humping your leg then I doubt a dog will have wet dreams but how would I know.....I am a cat lol