In order to find out anticancer activity of Korean pepper (Capsicum annuum L.), the cytotoxicity against 8 cell lines including 293 (normal kidney cells) and A-431 (epidermoid carcinoma cells) of extracts by extraction solvents and plant parts were investigated using MTT assay. Also the correlation between content of capsaicin known as anticancer ingredient and cytotoxicity of extracts from pepper were analyzed. The distilled water extracts from seed and germinated seed showed very high cytotoxicity against 6 cancer cell lines including A549 (lung carcinoma cells), AGS (stomach adenocarcinoma cells), HeLa (cervix adenocarcinoma cells), HepG2 (hepatoblastoma cells), HT-29 (colon adenocarcinoma cells), and MCF-7 (breast adenocarcinoma cells). But 80% ethanol and methanol extracts showed cytotoxicity against 293 and AGS. The RC50, that was, the concentration of sample required for 50% reduction of cell viability, of seed and germinated seed extracts against AGS were 33.4~389.1μg/mℓ and 63.9~1,316.7μg/mℓ, respectively, so anticancer activity was higher in seed than in germinated seed. In capsaicin contents, seed with high cytotoxicity and pericarp with a little cytotoxicity contained 47.4~1,260.0μg/g and 58.3~1,498.0μg/g, respectively. As these results, the correlation was not between cytotoxicity and capsaicin content.