The invention discloses a mobile power supply convenient to dissipate the heat and having a mobile phone clamping function. The mobile power supply comprises a first clamping plate, a mobile power supply and a second clamping plate, wherein the inner top end of the mobile power supply is provided with a sliding groove, the sliding groove is of a T-shaped structure, the bottom of the sliding grooveis connected with a sliding rod in a sliding manner by virtue of a return spring, the sliding rod is of a T-shaped structure, the left end and the right end of the sliding rod are respectively connected with a ball in a rolling manner, one side of the ball contacts the inner surface wall of the sliding groove, two positions, disposed on two sides of the sliding rod, inside the sliding groove aresymmetrically fixedly connected with a buffer, and the first clamping plate is welded on the top end of the sliding rod. Two ends of the mobile power supply are respectively provided with the movablefirst clamping plate and the immobile second clamping plate, and the first clamping plate and the second clamping plate can fix mobile phone which is in charging, so that the mobile phone is preventedfrom being separated from the mobile power supply in the charging process, and the normal charging is ensured.