To establish the differential diagnosis and treatment method in bovine ovarian cysts, specially ovarian cysts with corpus luteum, serum progesterone ($P_4$) concentration and ultrasonography for measuring the cystic wall thickness and diameter of cyst and corpus luteum were investigated from slaughtered cows with ovarian cysts. Ovarian cysts were classified 8 types by the number of cyst, cystic wall thickness and present of corpus luteum. Ovarian cysts with corpus luteum were 11 (13.6%) of 81 cows and ovarian cysts without corpus luteum were 70 (86.4%) cows. The incidence rates of 8 various types of ovarian cysts were as follows; 2Ba 33.3%, 2Aa 25.9% and 2Bb 14.8%, respectively The Incidence rates of ovarian cysts without corpus luteum were follicular cyst 59.2% and luteal cyst 27.2%. The cystic wall thickness were 2Ab 3.7mm and 2Bb 3.5mm, and the serum P4 concentrations were above 2.0 ng/$mell$ in IAa, tAb, IBa, 2Ab and 2Bb, respectively In ovarian cysts with corpus luteum, the correlation coefficients between corpus luteum area and serum $P_4$ concentration were 0.45. In ovarian cysts without corpus luteum, there was significantly positive correlations between cystic wall thickness and serum $P_4$ concentration($r^2$ = 0.54, p<0.01). These results indicate that $PGF_2$$alpha$ analogues can be choice for treatment of ovarian cysts with corpus luteum and above 3mm the cystic wall thickness because serum $P_4$ concentrations were above 2.0 ng/$mell$ in ovarian cysts with corpus luteum and thickened cystic wall. In conclusion, it Is suggested that ultrasonography is useful diagnostic tool for diagnosis and selection of treatment remedy in cystic ovaries of bovine.