Executives in the private and government sectors are alike in that they place a major emphasis on communication skills. However, there has never been any research done to investigate communication apprehension (CA) among Thai executives, especially to compare their CA when using Thai (L1) and English (L2). As a result, this study investigated the traitlike CA of 31 adult students in a master's degree program for executives in the political science faculty of a prestigious public university in Bangkok, Thailand, and administered t-tests to compare their CA in L1 and L2. The results indicated no difference in total traitlike CA among the students of this program when they communicate in L1 or in L2. However, the findings suggested that their CA in the category of interpersonal conversations in L1 was higher than that in L2. The findings are expected to enhance the English language teachers' understanding of the students in this executive program, which may improve the teaching and learning process.