The present invention relates, in general, to a charge equalization apparatus with series-connected battery cells and, more particularly, to a charge equalization apparatus, in which series-connected battery cells (B1 to BN) are connected in parallel with the primary windings (Mi 1 to M1N) of transformers (T1 to TN), switches (S1 to SN) for controlling the flow of current of the primary windings are connected in series with the primary windings (M1 1 to M1N), and multiple secondary windings (M21 to M2N) corresponding to the primary windings are connected in parallel with each other.