The major objective of the present study is to demonstrate how cultural knowledge affects language fluency.Two beginning-level Puerto Rican learners of Japanese, one with a high score on fluency, and one with a lower one, were given a test to assess their knowledge on some aspects of the Japanese culture. It was hypothesized that the one with higher fluency would get a higher score on the test, However, both learners did equally poorly on the culture test, which seemingly suggests no link between cultural knowledge and language fluency. Closer look of the results reveals that the strength of the fluent learner on the culture test widely diverges from that of the other. It is indicated that understanding certain aspects of the cultre is more influential on the leaners' fluency than other aspects.