Reaction calorimetry is one of the main thermal analysis techniques in chemical industry, which can provide a large number of effective data for safety assessment of reaction process. In the process of measuring reaction heat Qr, it is crucial to obtain the heat transfer factor between reactor and jacket, the current common measurement method is to calibrate before and after the reaction, but the results can not represent the dynamic change of UA in the reaction process. More accurate calorimetric data can be obtained by studying the continuous estimation method of heat transfer factor, which can provide safer and more effective guidance for the development of reactor and process optimization. Temperature oscillation calorimetry (TOC) is an effective method for continuous estimation of UA and Qr in laboratory scale small reactors. This paper summarizes TOC in detail from research history, principle, parameter calculation, simulation study and method evaluation, and the simulation results illustrate the advancement and applicability of this method. For larger reactors, state estimation approaches is a more widely used method for continuous estimation of calorimetric parameters. In this paper, three state estimation techniques, namely adaptive calorimetry, cascade calorimetry and extended Kalman filter (EKF), are reviewed, and the simulation results of continuous estimation of UA and Qr by EKF in reactors with different volumes are presented. Finally, the advantages, disadvantages and applicability of temperature oscillation calorimetry and state estimation approaches are compared and analyzed. On this basis, the technology of reactor calorimetry is prospected.