In Uganda, there has been a persistent phenomenon of low share of manufactured exports with no consistent explanation, despite improvements in macroeconomic environment, incentives and market access for the country’s exports, hitherto, regarded the cause for poor export performance. Existing statistics indicate that the share of manufactured exports has remained marginally low, estimated at under 4 percent. Uganda is a private sector-dominated economy with small and medium enterprises (SMEs) accounting for over 90 percent of the private sector (National Development Plan (NDP)-2010-2015 report, 2010). Consequently, the low export performance is a reflection of export performance of small and medium firms in Uganda. This study sought to examine the influence of firm characteristics on export performance, establish the influence of firm competencies on export performance, and determine the moderating effect of entrepreneurial orientation on the relationship between firm characteristics, firm competencies and export marketing strategy. The study also sought to examine the mediating effect of export marketing strategy on the relationship between firm characteristics, firm competencies and export performance. Lastly, the study sought to assess the joint effect of firm characteristics, firm competencies, entrepreneurial orientation and export marketing strategy on export performance of small and medium firms in Uganda. A cross sectional survey to establish the influence of selected firm factors on export performance was conducted using data collected from 76 small and medium firms in Uganda. The study employed multiple linear regression analytical techniques to establish factors that significantly influenced export performance of small and medium firms in Uganda. The findings show that nine factors, that is, frequency of travel abroad, number of export markets served, exporting experience of the firm, informational competencies, marketing and sales competencies, sole proprietorship dummy, product strategy, the managers’ exporting experience as well as diploma education dummy had a significant effect on export performance. These factors together accounted for 74.6% of the variance in export performance. The study revealed that foreign trips and breadth of markets greatly enhanced export performance of small and medium firms in Uganda. Thus, export decision makers need to enhance the capacity of their firms to undertake foreign trips and/or to expand export markets as a means of acquiring export market knowledge in order to create and deliver competitive products that meet the needs and requirements of export markets thereby enhancing export performance.