An isolating cabinet handcart provided with a live-line lock element comprises a cabinet body, and a relay instrument chamber, a breaker handcart chamber, a bus chamber and a cable chamber positioned in the cabinet body. In the breaker handcart chamber, the two ends of the same phase of an isolating handcart is additionally provided with a PT, and the secondary side of the PT is led to an electromagnetic lock. Thus, when operation of the handcart is locked electrically, the handcart is unlocked when being powered off, and the working safety and reliability are ensured effectively.