The time-resolved ESR (TR-ESR) signals of ground-state ((4)A(2g) of Cr(III) ion were observed in ruby and of Cr(acac)(3) doped in Al(acac)3 single crystals after irradiation with the second harmonic of a Nd:YAG laser at 77 K. At room temperature, TR-ESR signal was observed in ruby, but not in Cr(acac)(3). Both spectra at 77 K were of the emissive type; however, the intensity of the Cr(acac)(3) signal was very weak. The observed TR-ESR signal in ruby was changed from emissive polarity to an absorptive one at 700 mu s. The results of ruby and Cr(acac)(3) doped in Al(acac)(3) were explained by the initial emissive polarization and the recovery absorptive polarization from the excited state E-2. The spin polarization in the sublevels of the ground state was very long (about 500 mu s).