The photos were among private information stolen from the players' email accounts, the Los Angeles Times reported Monday.
Tyler Schrier, 23, of Menlo Park pleaded guilty to conspiracy, extortion and unauthorized access to a protected computer to obtain information. He was sentenced to 42 months in prison.
As part of his plea, Schrier admitted guilt in a similar plot in which he extorted $26,000.
An accomplice, Keith James Hudson, 39, of San Jose pleaded guilty to stealing naked photographs from a player's email by hacking the account. He then worked with Schrier to extort poker players, prosecutors said.
In 2010, the pair hacked the email account of Joe Sebok and stole intimate emails and photographs. They threatened to post them on the Internet unless Sebok and others paid them hundreds of thousands of dollars, prosecutors said.
No payments were ever made and Schrier sent an email containing a nude photo of Sebok to about 100 people.
Addressing the court at the hearing, Sebok said the extortion plot had "instantly damaged my ability to sustain my livelihood doing what I had been since 2005" and caused him to lose endorsement contracts.