Previous studies have observed a paradigm shift in the debate concerning the dimensionality of organizational citizenship behavior. Building on organizational citizenship behavior literature, the present study in intends to validate the dimensionality of the organizational citizenship behavior (OCB) scale developed by Smith et al., (1983) who proposed a 2 dimensional16-item instrument. Data was collected through a survey questionnaire using systematic random sampling technique to employees of local government in Lagos State, Nigeria. A total of 400 questionnaires were administered and 393 valid responses were obtained over a period of 4-weeks. Factor analysis and reliability analysis were conducted to confirm that the instrument is valid within the context of local government employees. The implication of this current study is that OCB scale developed by smith et al., (1983) has revealed two-dimensional structures comprising of; altruism and generalized compliance. The instrument was found to be valid and reliable scale for OCB measurement among employees of public organization, particularly Local Government employees in Lagos, Nigeria.