This is a randomized, double blind, placebo controlled, cross-over, clinical trial to determine the effect of fish oil supplementation with Lovaza® on triglyceride levels in HIV-infected subjects on HAART with elevated serum triglycerides. The sample size is 40 subjects. The total duration of the study is 28 weeks, with 12-week treatment periods separated by a 4-week washout. This study will be conducted at the Clinical Research Center at Tufts Medical Center.