Background: Laos has a high prevalence of hepatitis B infection, at about 8% of the population. Hepatocellular carcinoma (HCC) caused by this virus could be significantly reduced by the primary prevention and early treatment of patients with chronic hepatitis B. Objective: To describe the levels of viral load in patients with chronic Hepatitis B before and after antiretroviral (ARV) treatment in Lao PDR. Methodology: A retrospective descriptive study was conducted by reviewing the laboratory records of 135 patients with chronic hepatitis B registered from January 2010 to August 2013 at the Christrophe Merieux Infectiology Centre, Vientiane Capital, Lao PDR. Hepatitis B viral load (VL) was determined by PCR before and after treatment initiation among this population. Pearson chi-square and Wilcoxon tests were used to compare the proportions and geometric mean. Result: Among 135 hepatitis B patients, most (88%) of the patients were from referral hospitals in Vientiane Capital. 65% were male, and 55% were given ARV without VL testing. Among these, Cycloferon (an immunomodulator) was the commonly used (57%), which is not yet recommended by the Asian Pacific Association for the Study of the Liver Guidelines (APASL). The VLs of patients treated with ARV and Immunomodulator were significantly reduced from the baseline after 4 months. Patients treated with ARV alone had significantly lower geometric mean VL [IC 95%] 4 months after treatment initiation than those treated with Immunomodulator (3.53 [2.81-4.2] versus 4.14 [2.99-5.29]; p<0.001), and those treated with a combination of ARV and Immunomodulator (Geometric mean of VL: 3.53 [2.81-4.2] versus 4.82[3.8-5.8]; p=0.035). Our study found that there was no significant difference in VL between Immunomodulator and ARV+ Immunomodulator (4.14 [3-5.2] versus 4.82 [3.8-5.8]; p=0.371). Conclusion ARV and Immunomodulator treatment is effective in reducing HBV VL, but ARV works more effectively than when used in combination with Immunomodulator and for Immunomodulator alone. There is an urgent need of developing Lao consensus hepatitis B treatment guidelines and good clinical practice implementation.