This study uses the recordings of Japanese native speakers’ natural conversations as the research data to investigate the usage of Japanese filler “Maa”. Comparing the conversations between students and their friends with those between students and teachers, the results indicated that 1. teachers use “Maa” more often than students, and when students talk to their teachers, they are not consciously avoiding “Maa” 2. in student-friend conversation “Maa” is prone to appear when speaking with confidence, in student-teacher conversation, people use “Maa” to make others feel him humble. Analyzing the student-teacher conversation, the result shows that “Maa” tends to appear in utterance with meta-consciousness. Specifically, it is an utterance that tries to show him humbly, or a comment from a meta-perspective, and it often appears in the form of supplementary utterance. Also, the meaning of “Maa” cannot be sought, it should be considered in the form of specifying an environment in which it appears easily.