The aim of this work was biological treatment of agroindustrial waste (P1), biowaste (P2) and biodegradable municipal solid waste (P3) by the composting process in adiabatic reactor during 21 days. In experiments P1, P2, and P3, a maximum temperature of 52, 55, and 57 degrees C was reached, and the thermophilic phase lasted 8, 5, and 6 days. The cumulative evolved CO2 and NH3 was 122, 407, and 389 g kg(VM0)(-1) and 89, 148, and 559 mg kg(VM0)(-1), respectively. The pH value at the beginning of the process was in the neutral and at the end in the slightly alkaline domain. The substrate humidity increased by about 5 %, while the C/N ratio decreased due to a decrease in the organic C content and an increase in N content. Consequently, a conversion of 48 %, 71 %, and 56 %, respectively, was achieved in experiments P1, P2, and P3.