Reading culture is one of the most discussed issues in the world, because it affects performance of students in schools. Libraries have an influence in promoting academic achievements. The purpose of this study was to assess reading culture and academic performance on Kiswahili subject among secondary school student in Ilemela municipality. The study adopted a mixed research method and convergent research design. Study sample size consisted of 370 O level secondary school girls and boys aged 16-18 years as well 19 teachers were chosen using random sampling as well as DSEO 1. This study used, Interview with key informants in schools and focus group discussion was also conducted in this study. The finding revealed that student who practiced good reading culture feel comfortable to read their books always and they are likely to perform better in their education pursuits. It was recommended that Reading should be compulsorily emphasized at all levels of education; it should be part of pupils and students evaluation at the primary, secondary and tertiary tiers of education. Therefore, parents should have a vital role to play in developing the reading culture in their children. They should establish a monitoring mechanism to assess the state of readership of their children. They should create a conducive reading environment for their children in their home.