The invention relates to a biomass burner. The biomass burner is characterized in that biomass is fed from above, a telescopic ignition manner is adopted, and the space of a furnace is fully utilized through upper feeding; a vertical structure can be adopted, so that the occupied area of the burner is decreased; the problem that an ignition device is positioned in the furnace for a long time and is liable to damage is solved through telescopic ignition; and the biomass burner has the characteristics of being reasonable in structure, efficient and clean to use, and low in maintenance cost.