Property of the phase of the reemitted field in the semiconductor quantum wells (QWs) excited by femtosecond pulse train is investigated. It is shown that the phase evolution of the reemitted field is controlled by the relative phase between the successive pulses of the incident train. For all the odd pulses excitation, the reemitted field is from out-of-phase to in-phase, then again to out-of-phase with the incident pulses, whereas for all the even pulses excitation, the situation is the opposite, i.e., it is from in-phase to out-of-phase, then again to in-phase with the incident pulses.