We analyzed the usage of the Japanese filler “Maa” in university lectures and found that it is concentrated when the speaker talks about his (her) own experience or opinion. The subject of this thesis is to explore why “Maa” is concentrated around when the speaker is talking about themselves. In order to understand this topic, we used natural conversation as a reference. As a result, we found that speakers are resistant to telling their own stories in their lectures, and the tension they feel at this time makes them use “Maa”.