A conceptual design of a micro heat pipe cooled reactor was proposed. In the conceptual design, the reactor core consists of TRISO fuel and a monolithic graphite block. The thermal power of the micro reactor is 0.5 MWt and the electrical power is 100 kWe. The refueling cycle of the core is no less than 5 years. The reactor uses about 250 potassium heat pipes to remove heat from the core to the thermoelectric conversion system. The thermoelectric conversion system of the conceptual design scheme in this paper intends to use Stirling motors to convert the heat energy exported by the heat pipe into electrical energy, and the thermoelectric conversion efficiency is about 25%. Through calculation, the basic parameters of the conceptual scheme are reasonable and feasible. The radial and axial power distribution of the whole core is obtained. In the reactor thermal hydraulic analysis, the full core model is established. The steady-state heat transfer calculation and the heat transfer calculation under residual heat removal condition are completed respectively. The results show that under all operating conditions, the maximum core temperature is within the acceptable range.