Human immunodeficiency virus (HIV) is rapidly becoming a global health concern. Proteomics technology was employed to examine HIV infected plasma samples in an attempt to identify disease-associated proteins. By comparison with normal and HIV positive plasma samples, at least eight proteins were significantly changed in HIV infected plasma. In particular, apolipoprotein AI presents a heterogeneous change in expression level with different isoforms. Apolipoprotein AI could be a useful biomarker for HIV diagnosis.