Background: Entamoeba histolytica is a protozoan parasite and the causative agent of amebiasis. It is estimated approximately 1% of humans are infected with E. histolytica, resulting in an estimate of 100,000 deaths annually. Current treatment for amebiasis infection are known to have side effect such as nausea, headache, urine became dark color, and etc. Therefore new medicine is needed to overcome these side effects and natural product is a potential alternative as source of antiamoebic compounds. L-cysteine biosynthetic pathway is essential for various cellular activities, including the proliferation and anti-oxidative defense of E. histolytica. Since the pathway, consisting of three reactions catalyzed by serine acetyltransferase (SAT), cysteine synthase (CS, O-acetylserine sulfhydrylase), Nad˖kinase (NadK) are not exist in humans, they are a rational drug target against amebiasis.  Objective: This study aims to determine antiamoeba activities of various plant extracts. Materials and Methods: Plants collected from Balikpapan Botanical Garden in East Kalimantan, extracted gradually using hexane, dichloromethane, and methanol as a solvent. Screening of these plant extracts was done using three enzymatic assay methods, SAT1/CS couple assay, CS single assay and Nadk/NO1 couple assay. For SAT1/CS and CS assay, extracts mixed enzymes was incubated at 37^oC for 10 minutes, added acetic acid and nynhidrin reagent, incubated 95^oC, and read absorbance at 560 nm. For Nadkinase/NO1 couple assay, extracts mixed enzyme added with NADH, incubated at room temperature for 10 minutes and read absorbance at 490 nm. Results: Out of 114 plant extracts, there were 32 extracts, 13 extracts and 8 extracts showed inhibition >75% for SAT1/CS3 couple assay, CS single assay, and Nadk/NO1 couple assay, respectively. Two species plants showed inhibition >75% on SAT1/CS, CS, Nadk/NO1 enzymatic assay namely Melicope glabra and Cratoxylum sumantranum. According the reference, the chemical compounds contained in those plants are xanthone and benzophenone. Therefore, further research is still required to identify which compounds that take a role in antiamoeba activity. Conclusion: M. glabra and C. sumatranum potential as a candidate to be further examine as an antiamoeba drugs and will be continued for fractionation and purification the active compound.