Abstract: Based on the data from Huzhu Bamei species farm from 2000 to 2008,the analysis showed that breeding interlude in different variety was at 21.80 to 27.60 days,the average breeding interlude was 25.02 days,the breeding interlude decreased with the increase of fetus numbers,however there was no different signifcance at the same fetus number in different variety（P 0.05）.By analysis of 128 sows breeding at the same time in 2008,the result indicated that the empathema breeding intensively was at post-weaning 6～8 d in the same oestrus,and the conception rate also was high.Additionally,it was related to season to a certain degree with the feature that it is shorter in spring,summer,autumn and longer in winter.