No! Unequivocally no. Severus Snape is not Harry’s father. J. K. Rowlings, author of the Harry Potter series, went to a great deal of trouble creating unique characters who shared common connections. Professor Severus Snape was the head of Slytherin house. He was also a former Death Eater. While Dumbledore trusted him, Harry didn’t, and consequently neither did the readers. Suspicions were aroused at every turn by the level of enmity Snape felt toward Harry, but a piece of the puzzle was revealed when readers learned that Snape had a crush on Lilly who had eyes for no one but Harry’s father. Snape was not Harry’s father. One might consider Snape as a covert operative under deep cover, as the reader learns of his ultimate mission in the final book of the series.

Enotes has an extensive collection of Harry Potter reference material.

http://www.enotes.com/search?q=harry+potter