A PC system which can be applied to measure some important parameters of research reactors has been developed. It includes multi-counter, multi-scaler, reactivity computer, control rod drop time measurement and power calibration and solving any problems or difficulties when counters are used. Analog data acquisition is relatively well-known and has not been included in this work. The multi-counter and multi-scaler are basic tools for many kinds of research reactor experiments which replace conventional counter modules and MCAs. The reactivity computer can accommodate virtually all reactor power monitors. As the start-up channels can also be used, it can give reactivity values at the earliest stage of new reactor commissioning and can be used in critical assemblies as well. The control rod drop time measuring programme which replaces the use of memory oscilloscope. The power calibration programme offers improved accuracy and convenience. Refs, figs, 1 tab.