Canadian pop star Shawn Mendes has had enough with people talking about his sexuality online.

The 17-year-old Stitches singer set the record straight via his Snapchat account on Thursday, after scrolling through some YouTube comments suggesting that he gives off a "gay vibe."

"First of all, I'm not gay. Second of all, it shouldn't make a difference if I was or if I wasn't," he asserted.

"The focus should be on the music, not my sexuality."

Mendes acknowledged that "99 per cent of you guys aren't making assumptions like this," but he went on to call out the "one per cent of you that are."

"I just want you guys, before you judge someone on the way they speak or act, to think 'Hey, maybe I shouldn't be judging someone,'" he said.

The Juno-nominated singer-songwriter declared that he was frustrated because people were suggesting that he was gay "as if it were a bad thing."

He signed off with a simple, "I love you guys."

Mendes kicks off the North American leg of his largely sold-out world tour on July 15 in Florida, with Canadian stops planned in Vancouver on July 27 and Toronto on Aug. 21.