This study examines the relationship between entrepreneurial orientation (EO) and firm performance in a sample of 306 Vietnamese SMEs and 172 Thai small and medium-sized enterprises (SMEs). Dimensions of entrepreneurial orientation including risk-taking, proactivity and innovativeness are explored. The results indicate that Thai SMEs are more innovative and proactive than their Vietnamese counterparts, while Vietnamese SMEs are inclined to be more risk-taking. Thai SMEs have higher perceived business growth, job creation and net profit than Vietnamese SMEs.