The effect of the mechanical treatment of UO2(CH3COO)2·2H2O in a planetary ball mill in air or as a suspension in toluene or benzene on its crystal structure and coordination mode has been studied. No significant changes in the crystal structure are observed. IR-spectroscopy results suggest that in the part of the mechanoactivated material the bidentate bonding of the CH3COO− is transformed in monodentate one. The newformed species is soluble in non-polar solvents.