To establish the differential diagnosis and treatment method in bovine ovarian cysts, specially ovarian cysts with corpus luteum, serum progesterone concentration and ulrasonography for measuring the cyclic area, thickness of cystic wall and echogenicity of corpus luteum were investigated in cystic ovaries from slaughtered cows. The incidence rates of ovarian cysts were follicular cyst 69.2% and luteal cyst 30.8%. The incidence rates of 8 various types of ovarian cysts were as follows; 2Ba 32.3%, 2Aa 25.8% and 2Bb 14.5%, respectively. The thickness of cystic wall were 2Bb 3.93mm, 2Ab 3.70mm and 1Aa 1.93mm and the serum progesterone concentrations were above 1.0ng/$mell$ in 2Ab, 2Bb and IAa, respectively. The cystic area of ovarian cysts with corpus luteum was 288.30mm2, but ovarian cysts without corpus luteum 542.30$ extrm{mm}^2$, and the thickness of cystic wall 2.12mm and 2.40mm, respectively. The serum progesterone concentration was 1.91ng/$mell$ in ovarian cysts with corpus luteum and 1.20ng/$mell$ ovarian cysts without corpus luteum. There was not the correlations between thickness of cystic wall and serum progesterone concentration in ovarian cysts with corpus luteum, whereas, was the correlations in ovarian cysts without corpus. These results indicated that PGF2$alpha$ analogues can be choice for treating the ovarian cysts with corpus luteum because serum progesterone concentrations were above 1.0ng/$mell$ in ovarian cysts with corpus luteum. In conclusion, it is suggest that ultrasonography is useful diagnostic tool for diagnosing and choicing of treatment remedy in cystic ovaries of bovine.