To help promote existing regional brands and to gain more competitive advantages by encouraging behavior towards promoting regional brands (BPRB) from business owners, this article aims to examine the roles of resource advantage (RA), government policy (GP), consumer pressure (CP), and attitudes toward promoting regional brands (APRB) based on the theory of planned behavior (TPB) and the attitude–behavior–context (ABC) theory. Both the direct and indirect effects of RA, GP, CP, and APRB on BPRB are explored in the proposed conceptual model, where the field survey data are from business owners who participated in a regional branding process. A sample of 237 valid responses was used to perform partial least squares (PLS) regression. The results show that RA, CP, and GP significantly and positively impacted BPRB, where GP was the strongest influencing factor, followed by RA and CP. APRB was found to significantly and positively mediate the relationship between RA and BPRB, as well as between GP and BPRB. The findings of all the influencing factors and their rankings in motivating business owners’ behavior, as well as their revealed underlying mechanism, provide a useful theoretical and practical reference for promoting and advancing regional brands’ sustainability.