Abstract: A vacuum adiabatic calorimeter has been established in our laboratory. In order to ascertain the precision and the accuracy of the whole apparatus, the heat capacity of KCl was measured from 60K to 300K. The difference between the weights of the samples used in the two series of experiments is 18.6255g. Except for a few points, the deviation of the experimental points from the smooth curve does not exceed ±0.3 per cent.The selected values of molar heat capacity of KCl are tabulated from 60 K to 300 K, and are compared with the values given by other authors. Our result is in agreement with the literature values with the deviation not exceeding±0.3 per cent, which shows our calorimeter is reliable.The heat capacities of UO₂SO₄ and UO₂(NO₃)₂. 3H₂O have been measured from 60K to 300K by the above-mentioned calorimeter. No thermal anomalies were found. Except for a few points, the deviation of the experimental points from the smooth curves for the two compounds does not exceed ±0.2 per cent.