To provide an impeller having structure that assembly workability is excellent, in the impeller of a double suction type multi-blade fan formed so that a number of blades are situated in an annular state by rings on both sides of right and left and a central plate 10.

Slits are formed in a plate 10 annularly along an outer peripheral edge, a difference in level 3 is formed approximately in the central part of a blade 1 and a half part of the blade 1 can be inserted through the slit. Tongue pieces 2 are formed on the two ends of the blade 1 and the slits through which the respective tongue pieces 2 are inserted are formed in rings 20a and 20b. The blade 1 is inserted through the slits 12 by alternately changing right and left directions. The tongue pieces 2 are inserted through the respective slits and the tongue pieces 20 protruded through the rings 20a and 20b to the outside are caulked for assembly.