To provide a power generator which does not require raw materials made to be pellet, can use dry lumber from thinning, felled small stick, fallen leaves, and the like as fuels as they are just by making them chips, and can move in the mountain forest capable of supplying the raw materials at hand, and can provide inexpensive electric power and appropriately maintain moutain forests by realizing a biomass power generator of a simple configuration whose decomposition/assembly is quick and easy.MEANS FOR SOLVING THE PROBLEM: A biomass power generator includes: pressurized combustion means of biomass materials; drying means of chip biomass materials; dry chip charge means which charges dry chips for the pressurized combustion means; driving means which obtains a rotary force by high-pressure gas that is generated by the pressurized combustion means and is supplied via gas storage means; power generation means which has the driving means as a rotation source; and air pressurizing means which supplies the pressurized combustion means with pressurized air. These are made easy to decompose/assemble.SELECTED DRAWING: Figure 1