For a given thermoelectric refrigerator, the main factor that affects the cooling efficiency is the enhanced heat dissipation modes at the cold and hot ends. In this work, the temperature variations of radiators, coolers, and cooling space with time in the states of forced convection and natural convection at the heating end and the cooling end, respectively, were experimentally studied. The experimental results show that under the natural convection at the heating end, the relative temperature of the radiator continues to rise and the relative temperature of the cooler first drops to the minimum and then rises. When the experiment lasts 600 s, the radiator relative temperature and the cooler relative temperature are 26.05℃ and -3.97℃, respectively. Under the forced convection, the radiator and cooler relative temperatures were stable at 3.2℃ and -20.00℃, respectively. There is an optimal value for the amount of the heating end air flow, which minimizes the input power consumption of the cooling fan and the thermoelectric cooling and leads to the best performance of the thermoelectric cooling. When the cooling end is under forced convection, the maximum temperature difference between the cooler and the cooling space is 2℃, while under natural convection the maximum temperature difference is 7℃,which realizes the uniformity of the temperature in cooling space.