Assertive communication becomes a matter of concern in order that nurse practitioner can cooperate with others in various conditions. The nurse less motivated and showed bad attitude in collaborating with colleagues without good communication. The purpose of writing to identify the influence of assertive communication training to work motivation affiliation nurse practitioner at two regional general hospital in Southeast Sulawesi, Indonesia. This research using design a quasi experiment pre test - post test with control group, with sampling in proportional sample with the total sample 74 nurse practitioners, 37 people intervention group and 37 people the control group. The early stages for the intervention group will be pre-test and then given an assertive communication training in 6 sessions, after that do post test 1, the next 2 weeks after the training is done again post test measurement 2. The result showed change of work motivation affiliation pre-post test group significantly higher intervention either on post test 1 and post test 2 (p < α). The study recommended that nursing managers need to improve the work motivation affiliation of nurse through training so that the hospitals to provide satisfaction for patients in receiving nursing services.