The US rapper dated the reality TV star for several years before she struck up a relationship with Travis Scott after they split in April 2017.
Tyga is allegedly claiming he was still sexually active with Jenner around the time she would have conceived, according to Radar Online.
A source told the publication: “Tyga wants a DNA test because he really thinks that there is a chance this baby could be his.
“Tyga told friends that he was still sexually active with Kylie nine months ago, when this baby was likely conceived.”
In September Tyga appeared to claim he is the father of Jenner’s daughter, Stormi Webster.
The Rack City rapper posted “Hell nah, that’s my kid” on Snapchat as reports of Jenner’s pregnancy broke.
But he later retracted the statement, insisting it was a “fake story”.
Speaking to Metro he said: “I didn’t comment on anything, I didn’t comment on anything, it was a fake story. It’s all a fake story.”
Jenner welcomed her first child on February 1 after refusing to comment on reports that she was expecting with Scott.
The young businesswoman announced the news with a video tribute to her new daughter and a statement in which she apologised to fans for spending nine months in hiding.
Stormi is the latest edition to the Kardashian-Jenner clan following the birth of sister Kim Kardashian’s daughter Chicago in January.
Khloe Kardashian is also gearing up to give birth to her first child with boyfriend, and NBA star, Tristan Thompson later this year.
Standard Online has contacted a representative for Tyga for comment.