In order to evaluate the biodegradability of an organic waste, a specific respirometric tool was used, which allowed measuring the evolution of the biological oxygen uptake rate with controlled aeration conditions and constant temperature and moisture. The oxygen uptake rate was then modelled to quantify the easily biodegradable organic matter, the slowly biodegradable organic matter, the microorganisms growth and death kinetics and the hydrolysis kinetics. The influence of the temperature and moisture conditions on the evaluation of the biodegradability was determined by studying a mixture of sludge and pine barks (S1/PB) with four different moistures (15.0 %, 31.3%, 53.3%, 61.7%) at several temperatures (19.5 to 66.2°C). Then, the biodegradability of this first mixture was compared to the one of a second sludge mixed with crushed wood pallet (S2/CWP).