This study investigated several factors about the acquisition of Japanese lexical accent by English-speaking Japanese learners. Twenty-one adult learners of Japanese as a foreign language took a lesson online to learn the accent patterns of 40 target words. After the 1-hour lesson, they were asked to perform several tasks: take a written review test: read out actual Japanese words with immediate monitoring; read out nonsense words with immediate monitoring: and distinguish accent patterns. Correlation analysis revealed that the accuracy of lexical accent in reading out the target words showed a significant strong correlation only with the immediate monitoring score. The score with the review test failed to show a significant correlation with accent accuracy; however. it did show a significant correlation with the immediate monitoring score. These results were evaluated in terms of acquisition of lexical accent. It was evident that the instructed accent information was used for monitoring rather than in actual production, although accent knowledge is important in production. It is supposed that repeated monitoring and correction convert accent information to accent knowledge and that these processes lead to a gradual improvement in the accuracy of lexical accent.