This study was designed to investigate some factors related to job satisfaction of academic staff in Nigerian universities. A sample of 1142 academic staff from the three categories of universities were sampled. A questionnaire, validated and tested for reliability, was used for data collection. Simple percentage, mean, t -test and F ratio (ANOVA) were used for data analysis. The results show that the level of job satisfaction of the lecturers has generally increased over the past five years and that lecturers in federal universities have a higher mean job satisfaction score than those in state and private universities. The level of job satisfaction of the lecturers is significantly influenced by their sex and university status ( P <0.05).