NOVELTY - Preparing biological agent involves drying wheat straw and crushing into powder. The peanut shells are dried and crushed to obtain peanut shell powder. The wheat straw flour and peanut shells powder are added to a stirred tank and beans cypress and water are added where the mass ratio of wheat straw powder, peanut shell powder, beans cypress and water is 1:2:3:5, to obtain a paste. The mixture is taken in a reactor and stirred at 500 rotations/minute (rpm) for 15 minutes at 95 degrees C and reaction is kept for 30 minutes for natural cooling.    USE - Method for preparing biological agent for removing ammonia, nitrogen, sulfide, aniline substances and industrial chemical oxygen demand from sewage (claimed).    DETAILED DESCRIPTION - Preparing biological agent involves drying wheat straw and crushing into powder. The peanut shells are dried and crushed to obtain peanut shell powder. The wheat straw flour and peanut shells powder are added to a stirred tank and beans cypress and water are added where the mass ratio of wheat straw powder, peanut shell powder, beans cypress and water is 1:2:3:5, to obtain a paste. The mixture is taken in a reactor and stirred at 500 rotations/minute (rpm) for 15 minutes at 95 degrees C and reaction is kept for 30 minutes for natural cooling. Zeolite is ground to obtain zeolite powder having particle size between 50-100 mesh and is mixed with humic acid in the weight ratio of 1:2. The chitosan and diatomaceous earth are crushed through 100-200 mesh and chitosan, diatomite and glycerine are mixed in the mass ratio of 1:1:1. Rhodococcus, Micrococcus luteus, Enterococcus faecalis, Acinetobacter baumannii, a crystal Arthrobacter, bacterium Pseudomonas fluorescens and nitrogen sulfur Bacillus are mixed and cultured at a concentration of 1X108/ml of the fungus liquid in the volume ratio of 10:7:5:3:3:2:1. The obtained culture is mixed uniformly with earlier obtained paste in the mass ratio of 1:1 and cultured at 30 degrees C for 12 hours. The mixture of zeolite and humic acid, and the mixture of chitosan, diatomite and glycerine are added to the culture and stirred for 3 minutes at 100 rpm. The obtained culture is dried at 20-22 degrees C to a water content of 10-12% to obtain the biological agent where the mixtures are added in the mass ratio of 1:2:3:5.