This study aimed to analyze the effectiveness of literacy learning media based on letter bowling games to improve the early literacy skills of children aged 5-6 years in Rembang. The research method used in this research is Research & Development, proposed by Borg and Gall with ten stages. The population in this study was group B kindergarten children; the samples in this study were group B children Kindergarten Pertiwi 2 Kaliapang Village, Kindergarten Pertiwi 1 Kaliapang Village and Kindergarten Pertiwi Sumbermulyo, all of which amounted to 45 children. Data collection techniques using observation, questionnaires, interviews, and documentation. Meanwhile, the data analysis used quantitative descriptive analysis, requirements test and t-test. As a result, the development of the letter bowling game is effectively used to improve the early literacy skills of children aged 5-6 years in the Rembang district with a t-test of 21.189 and a t-table of 4.381 or 21.189>4.381. In contrast, the N-gain value is 71 in the practical category.