This study assessed the innovative capacity of SMEs in South Western Nigeria through the analysis of the factors that determine their innovative capacities. Specifically, the following innovative factors were assessed; Size of the firm, Age of the firm, Level of employee training, Collaboration, and Entrepreneurship. One hundred and twenty SMEs were purposively selected from the database of National Association of Small and Medium Scale Industrialist and the directory of Small and Medium Enterprises Development Agency (SMEDAN), from Ogun and Lagos States. The SMEs selected are those into manufacturing, construction and service industries. A total of 120 copies of questionnaires were sent to these firms, and 51 were returned representing 42.5% response rate. Multiple regression was used to empirically validate the research hypothesis of the study. The findings of the study revealed that Entrepreneurship is the most powerful factor that determines innovative capacity of a firm, also level of employees training is the second rated factor, while collaboration with other institutions, size of the firm, and age of the firm are other factors that influence firm innovative capacity in that order.