A superfield formulation is presented of the central charge anomaly in quantum corrections to solitons in two-dimensional theories with N = 1 supersymmetry. Extensive use is made of the superfield supercurrent, that places the supercurrent J µ α , energy-momentum tensor Θ µν and topological current ζ µ in a supermultiplet, to study the structure of supersymmetry and related superconformal symmetry in the presence of solitons. It is shown that the supermultiplet structure of (J µ α , Θ µν , ζ µ ) is kept exact while the topological current ζ µ acquires a quantum modification through the superconformal anomaly. In addition, the one-loop superfield effective action is explicitly constructed to verify the BPS saturation of the soliton spectrum as well as the effect of the anomaly.