British and Olympic diving champion and bronze medallist Tom Daley will return to host the show next year.
"I am over the moon to hear Splash! will run for a second season," Daley said.
"It's a dream come true for me to be involved in an entertainment show which has been so successful and also fits so well around my training schedule."
He added: "Splash! has put diving on primetime TV and diving clubs all across the country have kept telling me that they now have waiting lists, following the popularity of the show.
"That in itself is an incredible achievement and I'm very excited to be part of it."
ITV's director of entertainment and comedy Elaine Bedell added: "Splash! has proved itself by building a big, enthusiastic, primetime family audience.
"We've seen some quite incredible bravery from our celebrities this series, and the scale of the dives they were achieving is in no small part down to their mentor, and the star of our show, Tom Daley.
"We're looking forward to even more Saturday night spectacle, and sparkle, with the second series."
Splash! was ITV's highest-rating new entertainment series for five years and the first run was won by Eddie 'the Eagle' Edwards on Saturday.
Splash! live final - photo gallery: