This study investigated how learner beliefs relating to self-regulated learning were characterized and whether these beliefs changed over time during English self-study. Self-regulated learning functions effectively when supported by motivational beliefs, and many studies have confirmed its role in classroom settings; however, self-study which is detached from teachers and grades has not been examined. Two university students (Kei and Takushi) participated in the research and were willing to learn extra English through self-study. Using online material, they began to learn English independently. Over seven months, they set and reflected on learning goals. Thirteen semi-structured interviews were conducted, and excerpts regarding the participants' beliefs were extracted and categorized using qualitative thematic analysis. Five learner belief elements seemed to explain attitudes towards self-regulated learning during self-study. Kei displayed strong learner beliefs regarding the value of learning, the self, and learning management, which appeared to be the core ideas underpinning his self-regulated learning. Takushi also had a strong belief in language learning and its value, but sometimes these interfaced negatively, leading him to experience difficulty in conducting self-study based only on his own motivation.