The former Kilmarnock forward was available on a free transfer after rejecting the transfer of his contract to the newco Rangers.
“It is a great honour to be joining a club of Everton’s wonderful history and to have the chance to play with such a talented group of players in the world’s best league: the Barclays Premier League, in front of such a passionate group of fans,” Naismith told the club’s official website.
“I look forward greatly to working with the manager David Moyes and all the staff at Everton and working hard to deliver on the pitch to repay their, and the chairman Mr Kenwright’s, faith and belief in me.”
Manager David Moyes added: “We are delighted that Steven has agreed to join us. He will be an excellent addition to the players we already have and we look forward to him being fit and ready to play at the start of the season.
“He is an established international who can play in a number of positions. He has a flexibility we always like in our players and which will hopefully prove to be very useful for us.”
