The invention discloses a handcart interlocking structure used for a large current circuit breaker. The handcart interlocking structure used for the large current circuit breaker comprises a cross beam. A toggle plate is arranged in the middle of the cross beam. The left end and the right end of the cross beam are connected with the lower ends of connection rods. The upper ends of the connection rods are respectively connected with a locking rod. Each locking rod penetrates the lower lateral portion of a positioning box. A spring is arranged on each locking rod. Positioning wheels are arranged on two sides of the upper portion of the positioning box. The handcart interlocking structure used for the large current circuit breaker is an independent handcart locking device, retreating of the handcart with the large current circuit breaker when a short-circuit current passes is prevented, a simple and reliable mechanical interlocking structure is achieved on the handcart with the large current circuit breaker and locking of the large current circuit breaker is achieved in a working position, reliability and safety of operation are improved, and a guiding function is achieved with the handcart with the large current circuit breaker comes in or goes out. The handcart interlocking structure used for the large current circuit breaker is especially suitable for a large current circuit breaker with a rated current of 4000 A or above 4000 A and a rated short circuit breaking current of 63 kA or above 63 kA.