César Gastelum, 25, had more than half a million followers on TikTok. He went live on social media on Tuesday with two friends - all dressed as food delivery workers as part of a challenge.
In a video circulating online, a motorcycle with two people is seen stopping next to them, after which the driver shoots Gastelum in the head.
The killing took place at a shopping mall in the state capital, Culiacán, and has been confirmed by local police.
Sinaloa has been plagued by infighting between drug-trafficking groups for the past two years. More than ten drug lords have been killed in the state in recent years, according to local media.
