In this paper, we examined consumers' valuation of good agricultural practice (GAP), using a payment card contingent valuation method (CVM) and a contingent ranking method (CRM). A questionnaire survey was conducted in Sendai city, Miyagi prefecture, Japan. Responses from 200 participants were analyzed to measure the marginal willingness to pay (MWTP) for GAP in the case of tomatoes produced in Miyagi prefecture. The MWTP estimated from the CVM and CRM was 12.5 yen and 9.9 yen a piece, respectively. The MWTP for GAP estimated from the CRM in the case of tomatoes produced in Kumamoto was 9.5 yen, which was almost equal to the MWTP for GAP in the case of the tomatoes produced in Miyagi. This result leads us to the conclusion that regardless of place of origin, the MWTP for GAP seems to be approximately 10 yen a piece. The CRM was also used to explore the effects of respondents' characteristics on their valuation of GAP, based on 181 respondents. The respondents' sex and age influenced their valuation of GAP in the case of both Miyagi and Kumamoto. While the respondents who had a tendency to purchase agricultural products produced in Miyagi increased their valuation of GAP for Miyagi, those who purchased tomatoes almost every day decreased their valuation of GAP for Kumamoto.