This work presents the application of a cobalt and manganese mixed oxides-based catalyst with spinel structure to the decomposition of the storable green monopropellant H(2)O(2)90 wt%. The 5.4 % Co0.5Mn2.5O4/Al(2)O(3)catalyst was tested in a series of continuous and pulsed 2 N thruster firings, yielding a fast and repetitive performance, spontaneously and completely decomposing H(2)O(2)90 wt% without undergoing deactivation or fragmentation during the tests. A specific impulse of 104 s and a characteristic velocity of 881 m/s were reached, so that the characteristic velocity efficiency amounted to 93.7 %. The adiabatic decomposition temperature of the monopropellant (756 degrees C) was also reached, thus evidencing the effectiveness of the 5.4 % Co0.5Mn2.5O4/Al(2)O(3)catalyst. Its excellent activity in the decomposition of H(2)O(2)90 wt% was attributed to the presence of the redox pairs Mn2+/Mn(3+)and Co2+/Co3+, therefore making it a feasible material for low and medium thrust propulsive systems.