Getty

A popular streamer was allegedly assaulted at TwitchCon -- a convention where the biggest names on the platform interact with fans ... and, she's pissed at what she feels was a lapse in security by the brand.

Here's the deal ... yesterday, the streamer Emiru held a meet-and-greet at the festival in San Diego, where fans could walk up, chat with her for a moment and take a pic -- pretty standard fare for these types of conventions.

During the event -- as video circulating around social media shows -- a tall man walks forward and grabs Emiru ... bringing her face very close to his.

A worker -- who Emiru has since said is a member of her own security -- shoved the dude away before shooing him from the area while people go to check on her. X / @Emiru

Twitch released a statement

See Full Page