ABSTRACT Purpose: To carry out a systematic review of scientific productions that dealt with the topic of phonological processing in relation to the influence of poor academic performance, as well as its interference in the development of reading and writing. Research strategy: Articles published until August 2017 were searched in electronic databases. After elaborating the guiding question of the study: “What is the influence of phonological processing on poor school performance and its relation in the development of reading and writing?”, we collected and selected the reports using descriptors, gathered in a single search equation, according to three thematic axes: phonological processing, learning and poor school performance. Selection criteria: Original researches with an evaluation of at least two phonological processing skills were included. Articles that had no relationship between phonological processing skills and school performance were excluded. Data analysis: The titles and abstracts were read by two speech-language pathologists, separately. The results were compared and the divergences found decided by a third researcher speech therapist, also responsible for the study. The articles included were read in full and data extraction was performed to analyze the methodology and the main results. Results: 982 potentially relevant studies were selected. After using the evidence matrices, 38 scientific productions were included for detailed analysis. Conclusion: The study of scientific productions revealed that the alteration in phonological processing skills presented a relation with poor academic performance and, together with the schooling phase, directly influenced reading and writing skills.