Abstract: A converting circuit and a charging apparatus and relates to the field of electronic technologies. In the converting circuit, two groups of parallel connected primary-side converting circuits are connected in a one-to-one correspondence with a primary side of a first transformer and a primary side of a second transformer, and two groups of parallel connected secondary-side converting circuits are connected in a one-to-one correspondence with a secondary side of the first transformer and a secondary side of the second transformer, and the two groups of parallel connected primary-side converting circuits or the two groups of parallel connected secondary-side converting circuits include a first input end and a second input end separately connected to a primary side of a third transformer. Therefore, a primary-side converting circuit does not need to be disposed for the third transformer, to effectively reduce circuit complexity and reduce the circuit costs.