The 24-year-old moved to Elland Road on loan two years ago from Sporting Lisbon, before making the move permanent last summer.
However, Sacko made just 18 appearances in all competition for Leeds last season, and has not been involved in any of the Yorkshire club's pre-season friendlies this summer.
On Tuesday evening, Las Palmas announced that the Mali international had been signed for the remainder of the season after passing his medical.
"Blue and yellow will remind me of my good time in Leeds, but I have to play more now. Thanks for everything," Sacko wrote on his personal Twitter account.
The Gran Canaria club finished 19th in La Liga last season and will be playing in the Spanish second tier this term.