We investigated the temperature effect on exciton localization in self-organized InAs quantum dots. Quenching energy for excitons in reference quantum well and quantum dots was found to be 2 and 7 meV, respectively. Thermoactivation energy of electron-hole emission through a GaAs barrier in the quantum dots was measured as 46 meV. We observed an unusual decrease of photoluminescence peak full width at half maximum with temperature, suggesting suppression of nonpredominant size quantum dot emissions due to carrier tunneling between nearby dots.