Abstract: In order to develop high performance portable power sources, a mesoscale combustion powered thermoelectric generator (MCP-TEG) was designed and tested. Multistage backward flame stabilizing, flue gas reversing, and staggered pin fins for heat transfer enhancement, were designed to facilitate the integration of fuel pre-mixer, pre-heater, combustor, flame stabilizator, heat collector and heat spreader. Experimental results found that the present MCP-TEG was able to generate electric power of 29.6 W, which was larger than previous reports, and the corresponding power generation efficiency was 2.84%. The influences of combustion power, equivalent ratio, cold-end cooling condition and thermal insulation setting on the performance of MCP-TEG were comprehensively explored. An optimized equivalent ratio of 0.95 was found to obtain the maximum electric power. For water cooled MCP-TEGs, enhancing the cold-end cooling is not necessarily to augment the net electric power. Furthermore, the thermal insulation setting of MCP-TEG is critical, that is, the addition of a 3 mm layer of insulation is capable of increasing the electric power and power generation efficiency by 4.6% compared to that without insulations.