The 29-year-old has been with Roma since 2015, but he has only made 14 appearances for the Serie A outfit, spending time on loan with CSKA Moscow, Newcastle United and Basel over the last two seasons.
Last term, Doumbia scored 20 times in 25 appearances in the Swiss Super League, and he will now be given the chance to impress in Portugal after signing a 12-month loan deal with Sporting.
"It is a great pleasure to have arrived at this great club. I am very happy because I arrived a few days ago and was very welcomed by everyone," Doumbia told Sporting's official website.
"I do not want to create false expectations but I have not come to spend holidays and I will prepare myself in the best way, in this pre-season, and after that it will soon be seen."
Sporting, who will have the chance to make the move permanent at the end of the 2017-18 campaign, are 18-time winners of the Primeira Liga, but they have not landed the top prize in Portuguese football since 2002.