Many young children still experience reading difficulties when they enter school age. This study aimed to examine the effectiveness of a mixed methods-based reading literacy program (computer-assisted reading, independent tiered reading, and group-based reading teaching) to improve reading comprehension skills, vocabulary mastery, and reading fluency among early grade students. The study used a quantitative approach with experimental research methods. A quasi-experimental design was used to achieve the research objectives by involving 350 elementary school students who were in the fourth to sixth grade range of elementary school. The sample selection in this study involved the purposive sampling technique using several criteria. The teachers involved in this study totaled 150 teachers from 8 schools who acted as program implementers at school. The reading literacy program was implemented for two semesters for five days each week. The research findings show that the mixed methods-based reading literacy program had a significant effect on all competencies (word reading efficiency, reading comprehension ability, and reading fluency) in Grade 3 students, but this increase in ability was not seen in grades 5 and 6 students. More specifically, the effect size of the intervention on oral reading fluency in Grade 3 students was greater than the effect size in Grade 5 students. Furthermore, the effect size in Grade 4 was greater than the effect size in grades 5 and 6. This is because the treatment of reading difficulties in younger students is easier and more effective than in older students. In addition, based on the results of the correlation analysis, the number of words read during reading activities using a computer had a positive relationship with word reading scores and visual word reading efficiency in the post-test phase. Therefore, mixed methods-based literacy programs have a significant impact on reading fluency, and on vocabulary mastery and reading comprehension competence and reading fluency. This research has implications in that improving reading ability in the early grades is better done by using a combination of methods, such as computer-assisted reading, independent tiered reading, and group-based reading teaching. In this way, the improvement of students’ reading skills is more optimal.