This study, entitled the effect of poster alphabet media on early childhood literacy skills during the COVID-19 pandemic, single case experiment aims to recognize various alphabet letters ranging from letters A-Z, vowels, consonants as a whole and develop children's literacy skills. The hypothesis proposed in this research is to use poster alphabet media through Microsoft Power Point. The population in this study were 26 students with 2 students as the subject. This study uses a single case experiment method with an ABA (Applied Behavior Analysis) design by adding a second baseline phase after the treatment phase. On the results of the assessment after being subjected to treatment, the literacy abilities of subjects A and B increased from a score of 19 to a score of 24. Data collection used an observation sheet on the ability to recognize letters, documentation, and drawing conclusions. The results of data analysis that have been used show that the poster alphabet media method is hereby stated that it is quite influential on children's literacy skills and the introduction of letters a-z, vowels, and consonants as a whole.