It is found from the investigation that interpersonal communication and frequency of communication between agricultural promotion officers and Karen residents affect the level of acceptance of the innovations of lowland rice cultivation, while neighbors and village elders have little role in their acceptance. People medium in the form of village leaders influences villagers in communication with outsiders or in external activities. However, the decision to accept the innovations is a personal matter with the whole family participating in the decision process, based on individual readiness, suitability and possibility. The roles of the officers in the level of acceptance were effective only on village leaders who have frequent interpersonal communication with them.