Cancer patients undergoing chemotherapy generally have many side effects that cause physiological coping strategies to be able to adapt and psychological side effects such as anxiety. Social interaction in the form of social support obtained from family plays a role in adaptation to cancer patients. This study aims to examine the relationship of family support and coping strategies with anxiety. The samples were 102 cancer patients undergoing chemotherapy at the Hospital Dr. Pirngadi Medan.(1) The family support received cancer patients, more than half receive family support were medium as many as 54 people (53.0%). Coping strategies that use strategies Problem Focused Coping (PFC), more than half strategy PFC were medium as many as 56 people (54.9%). Anxiety experienced cancer patients, more than half anxiety was medium as many as 53 people (51.9%), (2) There is a negative relationship between support families received with experienced anxiety (r = -0.646; p<0.05), meaning that the higher the family support received by the diminishing anxiety experienced by cancer patients who are chemotherapy, there is a negative relationship with the strategic PFC use of anxiety experienced by cancer patients which chemotherapy (r = -0.545; p<0.05), meaning that the higher use of PFC strategy then decreased anxiety experienced by patients with cancer chemotherapy. Based on the results of this study concluded that there is a relationship of family support received and the use of PFC strategy with anxiety in cancer patients whose chemotherapy. The results of this study can be input to health care to help improve family support received and the use of strategy PFC with decreased anxiety in cancer patients undergoing chemotherapy treatment.