<p>The present invention relates to a steam boiler system using a pellet. The steam boiler system comprises: a combustion part burning a pellet to generate combustion heat, a steam generation part receiving the combustion heat generated in the combustion part to generate steam; a heat exchanging part cooling waste heat remaining after the steam is generated in the steam generation part; and a ventilating part supplying fresh air to the combustion part to achieve complete combustion. Therefore, optimum efficiency may be achieved by the complete combustion of the pellet. The steam boiler system comprises the combustion part (10) receiving a pellet to generate combustion heat; the steam generation part (20) heating water by using the combustion heat generated in the combustion part (10) to generate steam; the heat exchanging part (30) cooling waste heat remaining after the steam is generated in the steam generation part (20); and the ventilating part (40) supplying air to the combustion part (10) to achieve complete combustion when the pellet burns. The combustion part (10) comprises: a first housing (110); a pellet supply means (120) supplying a pellet to the first housing (110); a driving means (130) included in the first housing (110) to uniformly spread the pellet injected through the pellet supply means (120); and a fuel intake (118) supplying combustion heat generated as the pellet is burned in the first housing (110) to the steam generating part (20).</p>
