Abstract: Lead (Pb2+) is a toxic heavy metal causes oxidative stress that affect vital organs in the body, such as kidneys. Lead (Pb2+) induces formation of free radicals on cells, generation of Reactive Oxygen Species (ROS), Reactive Nitrogen Species (RNS) and decreases level of endogenous antioxidant defense mechanism. Oxidative stress triggers synthesis of Heat Shock Protein (HSP) as sublethal response. The imbalance level between oxidant and antioxidant defense mechanisms has been suggested to play an important role in cells death. Administration of exogenous antioxidant from plant, such as liverwort (Marchantia polymorpha L.) assumed can decrease free radical levels caused by heavy metal. The objective of this study was to investigate antioxidant activity of liverwort and to investigate whether methanol extract of M. polymorpha was affect HSP70 expression and NO production in base-line levels on HEK293 (human embryonic kidney) cell line. The DPPH was used to determine antioxidant activity, Griess assay to quantify nitric oxide and Western blotting was used to detect HSP70 expression. The result showed that the activity of antioxidant scavenger of liverwort is about 5.22 μg mL–1 of IC50 value. In addition, liverwort extract can increase cell viability and decrease NO production significantly between Pb(NO3)2 and treatment group and also decrease HSP70 expression attained to base-line level.