We present time-resolved photoluminescence investigations of InAs/GaAs structures containing quantum dots with the ground state at 1.43 eV. State fllling efiect and a Pauli blocking efiect were clearly observed. These efiects signiflcantly in∞uenced dynamics of excitation transfer from upper to lower state inside a dot leading to non-exponential dynamics. Numerical model based on nonlinear rate equations was proposed. The model described well the experimental data providing values of: lifetime of the ground state 0:53 § 0:03 ns, lifetime of excited state (when the ground state is full) 1:1 § 0:2 ns, and internal relaxation time (when the ground state is empty) 0:07 § 0:01 ns.