Abstract. We will discuss the complex energy and intensity dependence of the pulse profiles of a set of transient HMXB pulsars. We have detected strong energy dependence of the pulse profiles for these pulsars during outbursts. The pulse profiles are double peaked up to 10 keV and have a single peak at higher energy. We find that the energy spectra can be well fitted with a partial covering powerlaw model with high energy cut-off and an iron fluorescence line emission. The pulse phase resolved spectral analysis shows that the partial covering and high energy cut-off model parameters have significant changes with the pulse phase explaining the complex energy dependence of the pulse profiles.