The purpose of this study was to explore the possibility of targeted molecular therapy with anti-epidermal growth factor receptor (anti-EGFR) antibody (cetuximab) for the treatment of mucinous ovarian carcinoma. We analyzed EGFR protein expression and KRAS gene mutations in 5 mucinous ovarian carcinoma cell lines RMUG-L, RMUG-S, MN-1, OMC-1 and MCAS and evaluated the in vitro and in vivo effects of cetuximab on each. EGFR expression was observed in all cell lines except for MN-1 cells, and a KRAS gene mutation at codon 12 was detected only in the MCAS cell line. Cetuximab inhibited RMUG-L and OMC-1 cell growth in vitro and completely blocked RMUG-L tumor growth in vivo. On the other hand, cetuximab did not affect MCAS cell growth in vitro and only partially reduced the MCAS tumor growth in vivo. These results suggest the possibility of targeted molecular therapy with cetuximab for mucinous ovarian carcinoma cells lacking a KRAS gene mutation.