Koeman, who was appointed last August by Laporta’s predecessor Josep Maria Bartomeu on a two-year deal, led Barca to victory in the Copa del Rey in his first season in charge.
But the Catalans finished a disappointing third in La Liga, prompting speculation the club were looking for a replacement.
Last month Laporta declared “a cycle has come to an end” and refused to back the coach publicly, saying the club needed more time to analyse the season.
But he brought the uncertainty to an end after the club agreed to ratify the coach’s future following a board meeting.
“After the period of reflection we asked for after last season, we’ve decided to allow Ronald Koeman to continue under the terms of his current contract,” Laporta told a news conference.
“We’re very satisfied with how the conversations have gone, it was important that we had this period to get to know each other and we have spoken very frankly with each other.
“I want to highlight the impeccable behaviour of our coach in this time and we’ve tried to find some solutions to little differences we’ve had and we believe this is the best outcome for Barca, for us and for Ronald Koeman.”