Sexual harassment in public workplaces is commonly reflected as an unwelcome sexually determined behaviour which can affect workers’ performance (Okeke, 2011). Despite the vivid problem of sexual harassment of female workers at public workplaces in Tanzania and Zanzibar in particular, there is no study which was done, specifically on the sexual harassment of women at public work places in Zanzibar, specifically on the types, causes and effects at public work places. The aim of the study was to investigate the prevalence of sexual harassment at public work places in Zanzibar. The study employed case study research design; where by the sample size of 50 respondents was drawn through purposive and simple random sampling techniques. The data for the study were collected through interview and questionnaire methods. Also, the data were analysed through statistics descriptive and thematic analysis techniques. The study concluded that there is sexual harassment in the public workplaces in Zanzibar. However, sexual harassment is a result of the nature and culture of man domination. The study recommends that the approaches used to curb the problem should be reformed to fit the cultural context of the people as some sets of behaviour forming sexual harassment are not universal; there is a need for reformulation of policies to conform to the culture of Zanzibar. Also, it is advocated that a broader study can be conducted to include other public places from other public institutions in Zanzibar so as to have a wider understanding about the causes of sexual harassment at the public workplaces.