We carried out magnetization loop measurements on melt-textured YBa2CuO7-δ sample at various temperatures with the magnetic sweep method by using a vibrating sample magnetometer(VSM). We derived the curves of, J(T,B),lnE-lnJ and thermal excited potential U0(T,B), and analyzed the magnetic response of this sample, especially the influence of field sweep rates to the second peak. The peak effect of the sample, as well as the factors affecting the magnitude and position of the second peak, is discussed.