Job satisfaction is a globally important factor in determining organizational climate and subsequent worker productivity. In Kenya, job dissatisfaction is a major concern as evidenced by teacher burnout and the strikes in the teaching fraternity. This study investigated the influence of self-esteem and selected demographic variables on job satisfaction of public secondary school teachers in Kisii Central Sub-County, Kenya. Objectives included to: determine the influence of self-esteem on job satisfaction. Influence of age on job satisfaction. Influence of teaching experience on job satisfaction. Gender differences in job satisfaction and influence of marital status on job satisfaction of public secondary school teachers in Kisii Central Sub-County, Kenya. Maslow's hierarchy of needs and Herzberg's two factor theories guided the present study. The study's target population consisted all 903 public secondary school teachers in Kisii Central Sub County. A sample of 306 was selected by stratified random sampling to obtain a sample that was representative from all the categories of secondary schools followed by stratification according to gender. For qualitative data, twelve secondary school principals were purposively selected. The study adopted a convergent parallel research design with mixed method research approach. Data collection tools were questionnaires (modified Sorensen self-esteem scale and job descriptive index) and interview schedule. Validity was ensured by the assistance of the two supervisors' judgment. Reliability coefficient was computed using Cronbach's Alpha and it was found to be 0.764. Quantitative data was organized using the Statistical Package for Social Sciences (SPSS) version 20.0 and the data was analyzed using both descriptive and inferential statistics. Qualitative data was analyzed using Thematic analysis. Correlation analysis established a weak but positive (r =.203; p=.00 I < .05) correlation between teacher self-esteem and level of job satisfaction. Age had an influence on job satisfaction [F (3,258) = 3.31, p = .021]. Gender differences had an influence on job satisfaction where [t (144) = 2.061, p=0.041] with the female teachers favored as happier than the males. There was no influence of teaching experience in the level ofjob satisfaction [F (5, 256) =2.093, p=.067] and marital status had an influence on job satisfaction where the married were much happier in their jobs than the single. [F (4, 257) = 3.62, p=0.007.]. It was established that the self-esteem and the demographic variables of respondents accounted for 17 .9% of the variation in the level of job satisfaction, as signified by R square of .179; this is a fairly sizeable variation caused by the independent variables. From the findings, the study recommends that the secondary school principals should put mechanisms to ensure that male teachers have certain responsibility positions because female teachers enjoyed a relatively higher job satisfaction compared to their male counterparts. In addition, teacher counsellors should adopt appropriate cognitive behavioral therapy techniques to assist divorced and single teachers enhance their self-esteem and job satisfaction. This study recommends further research in gender and efficacy school management among secondary school principals. ln addition, qualifications and job retention among public secondary school teachers in Kisii Central Sub-County.