Hepatitis B Virus (HBV), a member of the Hepadnaviridae family, is a serious pathogen that causes chronic Hepatitis B and affects over 350 million people globally. Though a vaccine has been available since 1982, it cannot cure established infections and their effectiveness in preventing blood-borne transmission from an infected mother to her infant is only 90%. In order to better understand human HBV with the aim of finding effective treatments, much work has been dedicated toward investigating HBV virally encoded proteins. Unfortunately, few of these proteins have been able to be expressed or purified in vitro. As a result, current efforts seek to determine candidate HBV surface antigens as a possible immunotherapeutic target. Particularly promising candidates include those with identical function as HBV envelope L protein, which interacts with host proteins such as sodium-taurocholate cotransporters polypeptide (NTCP) and possibly epidermal growth factor receptor (EGFR) for entry. Meanwhile, current FDA-approved drugs to control human HBV target the viral polymerase. In order to develop more effective drugs against HBV infection, a better understanding of the HBV polymerase structure and function is necessary. Such information would not only inform us about the enzymatic mechanism of the viral polymerase, but also provide insights into the mechanism of current and mutation-mediated drug resistance. Here, we report the expression, purification, and analysis of the HBV LM envelope protein – a promising surface antigen. Lone LM was found to be an intrinsically disordered monomeric protein capable of interaction with host protein NTCP - and possibly EGFR. Addition of single-chain variable fragment 2H5 to LM formed a much more stable complex while conserving biological activity. Our results overall suggest that LM and the 2H5-LM complex exhibit favorable physical and biochemical properties for future in vitro study, in addition to serving a key role in promoting HBV entry and infection. We also demonstrate the expression and purification of the RNA dependent RNA polymerase domain and RNase H viral polymerase domains from different HBV species.