The Oilers released a statement on Saturday saying the team was deeply saddened by the loss of Pelss, who went missing Tuesday and was feared drowned in a river near his home in Riga, Latvia.
Local media had reported that Pelss jumped off a bridge and into the fast-flowing Daugava River.
"This is the news we feared. Kristians was an outstanding man and we feel terrible he has left us at such a young age," said Oilers general manager Craig MacTavish in a statement. "I can't imagine how painful this situation is for the Pelss family."
The club added that "details in regards to what led to this tragedy remain unclear."
Pelss arrived home in Riga on Monday after playing last season with Edmonton's top minor-league team, the Oklahoma City Barons of the American Hockey League.
He was drafted by the Oilers in the 7th round in 2010.