Abstract: Impeller design plays an important role in manufacturing centrifugal blowers because, without proper design, the blowers cannot function effectively. This paper presents design of the 12-blade backward-curved impeller to be used in the centrifugal blower for 40 kW wood chips gasifier. Design is mainly focused for the single-stage impeller. Required design parameters (such as impeller dimensions, blade shape, vane angle, number of blades for centrifugal blower) of the proposed impeller are calculated and the results are shown in this paper.