The invention discloses an anti-theft locking mechanism. The anti-theft locking mechanism comprises a container body, a container cover matched with the container body, and a security seal. The security seal comprises a cover body and an insertion portion, wherein the lower end of the insertion portion is a barb-shaped locking portion. A barb-shaped locking plate with a hole is arranged on a side wall of the upper portion of the container body, a barb-shaped elastic clamping portion is formed on the periphery of the hole of the barb-shaped locking plate, and corresponding locking holes are formed in the upper edge of the container cover and the upper edge of the container body respectively. When the locking mechanism is locked, the insertion portion of the security seal penetrates through the locking hole of the container cover and the locking hole of the container body, and the locking portion at the lower end of the security seal penetrates through the hole of the barb-shaped locking plate and is matched with and tightly locked with the elastic clamping portion. The container cover and the container body are connected with each other in an inserted mode and locked with each other through the security seal and the barb-shaped locking plate, the container cover can be opened only after the security seal is broken, logistics containers are prevented from being opened in the transportation process, and the anti-theft locking mechanism has a good theft prevention function. Meanwhile, the anti-theft locking mechanism is low in cost and simple in container sealing.