Reading is a requirement for success in the classroom today. Some problems that students face in learning English are they are not confident in answering questions and reading text. They show indications of low self-efficacy when learning English, especially in reading skills. Students' reading ability is influenced by various factors, including their self-efficacy. This research aims to explore what factors affect tenth-grade students’ self-efficacy and how self-efficacy affects students’ reading skills at SMAN 1 Padangan. This research was qualitative with a case study approach. The subject was tenth-grade students of X1 and X2. The data was collected by two instruments, interviews and reading tests. The interview was used to measure students’ self-efficacy and the reading test was used to measure students’ reading skills. This research shows that self-efficacy influences students' reading abilities. The findings in this research revealed that the majority of students answered in their interview with the researcher that the factors that influence student self-efficacy were interest, patience, a sense of self-confidence, character, motivation to learn, reward, and gender. Students who had a high sense of self-efficacy tended to be confident in working on questions so that their reading skills got a high score. It can be concluded that self-efficacy influences students' reading abilitiesKeywords: Self-Efficacy; Reading Skill; English Learning