Many water systems are under stress due to excessive depletion, but also pollution from anthropogenic activities, especially by toxic heavy metals. In order to protect and preserve water in nature, and thus the survival of people on Earth, it is necessary to develop an efficient, but also ecologically and economically acceptable method of heavy metals removal from water. In this diploma thesis, the effectiveness of solid waste/by-products (olive pits, olive pomace pellets, residues of sea urchins, cherry pits and sour cherry pits) from local plants for processing and food production for removal of lead from an aqueous solution (c o (Pb) = 2.959 mmol/L, i.e. 613 mg/L) by a batch process at different solid/liquid ratios (S/L = 0.25/50 - 2.50/50) was investigated. The highest capacity and removal efficiency were obtained at sour cherry pits, where at the highest S/L = 2.50/50 the lead was removed with efficiency of 90.9%. At the same time, the residual lead concentration was 55.5 mg/L, which is above prescribed values by Croatian laws (0.5 mg/L in the treated wastewater and 10 μg/L in the water for human consumption). Future research should be focused on the best possible utilization of biosorbents in multi-stage water treatment in order to reduce the quantity of the hazardous solid waste, as well as to reduce the lead concentration to permissible levels. Removal of lead from wastewaters using biosorbents could reduce the total costs of the water treatment and contribute to the concept of sustainable development.