This work examined access to healthcare services of the ethnic groups residing in Kanchanaburi province. A statistic survey was used to collect the data which were then analyzed to find out the difference in access to healthcare services among three groups of people: Thais, ethnic Thai residents and transnational ethnic migrants. The study findings revealed that the important factors affecting their access to healthcare services included health insurance, accessible medical centers, transportation convenience, and village types for the two kinds of ethnic groups. Other factors, e.g., ability to use Thai or being Buddhists, were secondary factors for their healthcare access, but ethnicity was not an important factor. The overall factors enabled Thais to have the most access, while the transnational ethnic migrants had the least access. The survey revealed that, if everyone had similar factors, they would be able to access and receive healthcare services equally.