Upon 4 K 11/2 excitation of Sm 3+ at 405nm, the performance of energy transfer from Sm 3+ to Eu 3+ in the red emitting phosphor CaMoO 4 :Eu 3+ , Sm 3+ significantly extends its excitation region for better matching the near-UV LED. Photoluminescence spectra indicate that the energy transfer pathway concerns the relaxation from 4 K 11/2 to 4 G 5/2 of Sm 3+ and subsequent transfer to 5 D 0 of Eu 3+ rather than 5 D 1 of Eu 3+ . The fluorescent decay pattern of Sm 3+ 4 G 5/2 level in CaMoO 4 :0.5% Sm 3+ , 2% Eu 3+ is studied at 77K based on the Inokuti–Hirayama formula, revealing an electronic dipole–dipole interaction between Sm 3+ and Eu 3+ . The coefficient for the energy transfer is obtained to be 8.5×10 −40 s −1 cm 6 . The fluorescence rise and decay pattern of Eu 3+ 5 D 0 level as Sm 3+ is only excited at 77K is well described by the dynamical processes of the energy transfer.