The purpose of this study was to examine relationships between emotional adjustment to advanced breast cancer, pain, social support, and life stress. The cross-sectional sample was compromised of 102 women with metastatic and/or recurrent breast cancer who were recruited into a randomized psychosocial intervention study. All women completed baseline questionnaires assessing demographic and medical variables, social support, life stress, pain, and mood disturbance. Three types of social support were assessed: (1) number of persons in support system; (2) positive support; and (3) aversive support. On the Profile of Mood States (POMS) total score, we found significant interactions between life stress and social support; having more people in the patient's support system was associated with less mood disturbance, but only among patients who had undergone greater life stress. Also, aversive social contact was significantly related to total mood disturbance (POMS), and having more aversive social contact was particularly associated with total mood disturbance (POMS) among patients who had undergone greater life stress. Pain intensity was associated with greater total life stress, and was not significantly related to social support. These results are consistent with the 'buffering hypothesis' that social support may shield women with metastatic breast cancer from the effects of previous life stress on their emotional adjustment; however, aversive support may be an additional source of life stress associated with emotional distress. Also, pain is greater among women with greater life stress, regardless of social support.