The complex formation of uranium(VI) with salicylhydroxamic, benzohydroxamic, and benzoic acid was investigated by time-resolved laser-induced fluorescence spectroscopy (TRLFS). We observed in all three systems a decrease in the fluorescence intensity with increasing ligand concentration. All identified complexed uranyl species are of the type M(p)L(q)H(r). In the uranium(VI)-salicylhydroxamate system a 1:1 complex with a stability constant of log beta(111) = 17.34 +/- 0.06 and a 1:2 complex with a stability constant of log beta(122) = 35.0 +/- 0.11 was identified. Also in the uranium(VI)-benzohydroxamate system the stability constants are determined to be log beta(110) = 7.92 +/- 0.11 and log beta(120) = 16.88 +/- 0.49. In the uranium(VI)-benzoate system only a 1:1 complex is existent with a stability constant of log beta(110) = 3.56 +/- 0.05.