The increased demand for forest products has led to an increasing scarcity of the earlier known and used tree species in the furniture industry. Consequently, it has led to the use of many ‘lesser-known'' tree species that are not recorded in conventional literature with several reasons. A study was conducted in Masaka municipality to enumerate the tree species used in the furniture industry using by administering questionnaire-guided interviews on systematically sampled furniture makers and identified key informants. The research observed that the most commonly used tree species, in order of greatest score to lowest score, were; Maesopsis eminii, Lovoa trichiliodes, Entandophragma angolense and Funtumia elastica. The lesser-known trees species included Xylopia eminii, Greveria robusta and Jacaranda mimosfolia. The major reasons for their use being their adequate availability. The factors affecting the use of the tree species included; Abundance and availability, information and awareness about their use, physical strength, customers'' tastes and preferences, carpenters'' tastes, cost effectiveness and profitability and government policy.