This work focused on the bioremoval of heavy metals by mangrove-derived Trichoderma biomass in the artificial sewage water. Of the 12 isolates tested, Hypocrea lixii TSK8 (JQ809340) was found to be a potent strain in removal of lead and iron. The bioremoval was enhanced through adsorption kinetics and process optimization using statistical model of the response surface methodology. The magnitude of Langmuir constant was 0.64 L mg−1 and 0.42 L mg−1 for lead and iron, respectively. Adsorption capacity was determined as 49.2 mg g−1 and 51.3 mg g−1 for lead and iron, respectively. The optimized conditions for maximum removal of lead and iron were standardized. The biosorption of metals was also confirmed by scanning electron microscopic and X-ray energy-dispersive spectrometer analyses. The results revealed that dried biomass of the H. lixii TSK8 was a potent biosorbent for efficient bioremoval of lead and iron.