Background: The benefits of Highly Active Anti-Retroviral Therapy (HAART) on mortality and morbidity in HIV-positive persons are well documented. The guidelines on When to start ART have evolved over the years towards earlier initiation of ART & present study was aimed to compare early versus late initiation of ART in PLHIV, in terms of effect on the CD4 counts and other laboratory parameters. Material and Methods: Present study was prospective, observational study, conducted in patients ≥18 years, of either gender, recently diagnosed with HIV-1 infection or PLHIV, with CD4 count ~ 500cells/cu.mm & patients with CD4 count~350 cells/cu.mm. Results: Enrolment of newly diagnosed clients for ART rose from 2.34 % in the L.I. group to 3.58% in the E.I. group & correlation was found to be statistically significant. In E.I group, median increase in CD4 count from baseline to 6 months was 119 cells/mm3 and from 6 months to 12 months was 57 cells/cu.mm. At 12 months of ART initiation, statistically significant deranged LFT, increased anemia was noted in the L.I group, as compared to E.I group. No statistically significant change in RFT, WBC count was noted.