The difference of spectral statistics properties between single-j and two-j shell models has been studied in the frame of the cranking model. The results show that the system becomes more regular when single-j space (i13/2)is replaced by a two-j shell (g7/2 +d5/2), although the basis size of the configuration space is unchanged. However,the degree of chaos of the system changes slightly when configuration space is enlarged by extending the single-j shell (i13/2) to two-j (i13/2 + g9/2) shell.