On Thursday, street vendors were selling discs marked with "Spider-Man 3" packaging, featuring a picture of the hero crouching in a black spider suit, and crediting stars Tobey Maguire and Kirsten Dunst in Chinese.
A copy bought for 10 yuan -- a little over $1 -- came with the vendor's caveat that it was "not good quality."
When played in a DVD machine, the screen showed a 2001 television movie "Earth vs. The Spider" starring Dan Aykroyd as a detective investigating the case of a spider-like killer.
Sony said in a statement that it had found no evidence of Spider-Man 3 DVDs on the streets in China or on the Internet, underscoring Hollywood's determination to fight Chinese counterfeiters, which they say costs them billions every year.
DVD shop vendors said it was still "too early" to obtain the fakes. The movie had its world premiere in Tokyo earlier this month, but will not be released in U.S. theatres until May 4.