The reaction of 2,4,5,7-tetranitrofluorenone with amines, thiols, and phenol in a polar aprotic solvent led to the preferable substitution of the nitro group in the position 2, and in the reaction of 2,4,7-trinitrofluorenone first the nitro group in the position 4 was replaced. The different regioselectivity is due evidently to the steric hindrances to the nucleophilic attack on the atom C-4 caused by the nitro group in the position 5 of tetranitrofluorenone.