Abstract: The principal types of two kinds of failures which are bending deformation or cracking of seamless steel pipes in hydrostatic test are described,the samples with failure defects taken from hydrostatic test are analyzed with a scanning electron microscope or an energy disperse spectroscopy respectively and some detailed pressures used for avoiding failure in seamless steel pipe hydrostatic test are proposed such as eliminating large inclusion concentration during steel making and casting,avoiding cracks occurred in steel pipes and minimizing imperfect structure during pipe rolling and heat treatment as well as strengthening the examination of hydrostatic testing equipment.