To establish the differential diagnosis and functional status in ovarian cystic cows, progesterone(P$_4$) and estrogen(E$_2$) level of cystic follicular fluid, ultrasonography for measuring the cystic diameter and thickness of cystic wall, and histological findings were investigated in cystic ovaries from slaughtered Korean native cows. Ovarian follicles were classified as systic if the diameter was greater than 25 mm by ultrasonography. Ovarian cysts < 3 mm of cystic wall thickness, < 10 ng/ml P$_4$ concentration and >10 ng/ml E$_2$ concentration were classified follicular cyst, ovarian cysts 3 mm of cystic wall thickness, 10 ng/ml P$_4$ concentration and <10 ng/ml E$_2$ concentration were classified luteal cyst, and ovarian cysts 3 mm of cystic wall thickness, < 10 ng/ml P$_4$ concentration and <10 ng/ml E$_2$ concentration were classified non-functional ovarian cyst, respectively. Also ovarian cysts were classified 8 types by anatomical and hisctological findings. Ovarian cysts with corpus luteum were 3 of 73 cows and ovarian cysts without corpus luteum were 70 cows. The incidence rates of 8 various types of ovarian cysts were as follows; 2Aa 56.2%, 2Ba 20.5% and 2Ab 15.1%, respectively. The incidence rates of ovarian cysts without corpus luteum were follicular cyst 76.7% and luteal cyst 19.2%. The thickness of cystic wall were lAb 3.9 mm, 2Ab 3.3 mm and 2Bb 3.2 mm, and the cystic fluid P$_4$ concentrations were above 10.0 ng/ml in lAb, 2Ab and 2Bb, respectively. There was significantly correlations between the thickness of cystic wall and cystic fluid P$_4$ concentration in ovarian cysts(p<0.05). The ovarian cyst was classified follicular cysts, luteal cyst and non-functional ovarian cyst by hormone analysis. The luteal cyst was accuratly dignosed by cystic wall thickness. But follicular cysts was misdiagnosed 13 cows of 56 cystic cows. The 13 cystic cows was determined as had non-fuctional ovarian cysts. The cystic fluid P$_4$ concentration was 3.3 ng/ml in follicular ovarian cysts and 30.1 ng/ml luteinized ovarian cysts. There was significantly positive correlations between thickness of cystic wall and serum P$_4$ concentration in follicular(r$^2$ =0.59, p<0.001) and luteal cysts(r$^2$=0.65, p<0.001). These results indicated that ovarian cysts had various stages of degeneration and luteal cyst was accuratly diagnosed measurement of cystic wall thickness by ultrasonography, but follicular cysts was not diagnosed only cystic diameter and cystic wall thickness. In conclusion, it is suggest that ovarian cysts was diagnosed by combination of clinical sign and anatomical cystic features.