A high performance liquid chromatography (HPLC) method has been developed for determination of 11 ginsenosides in black ginseng (BG, white ginseng that is subjected to 9 cycles of $95^{circ}C$ for 3 hr). After eluted by gradient elution of water-acetonitrile without buffer in 70 min, 11 ginsenosides in BG were identified. The proposed method provided good linearity ($R^2$>0.9995), accuracy (92.2-106.6%), and intra- and interday precision (RSD<2.6%). In addition, ginsenosides compositions in white, red, and black ginsengs were investigated using this method, respectively. Interestingly, in BG, the content of ginsenoside $Rg_3$ which does not existed in white ginseng was 7.51 mg/g, approximately 20 times than that in red ginseng.