A suction tube (1C, 1D, 1E, 1F) of a stratified scavenging engine including an air-fuel mixture passage and an air passage, an inlet side and an outlet side of each passage being connected to a carburetor and a cylinder, respectively, comprising: a cylindrical exterior member forming an outer perimeter portion of each of the air-fuel mixture passage and the air passage; and an interior member dividing an inside of the cylindrical exterior member into the air-fuel mixture passage and the air passage, wherein the interior member is attached to the inside of the cylindrical exterior member with use of elastic deformation of the interior member or of the cylindrical exterior member characterized in that the interior member has a tubular portion forming one of the air-fuel mixture passage and the air passage inside the cylindrical exterior member, an inlet side flange portion provided on an inlet side of the tubular portion, and an outlet side flange portion provided on an outlet side of the tubular portion, a portion between the inlet side flange portion and the outlet side flange portion of the tubular portion faces and contacts an inner perimeter surface of the cylindrical exterior member, and an inlet side fitting groove and an outlet side fitting groove into which the inlet side flange portion and the outlet side flange portion are fitted, respectively, are formed on an inlet side end portion and an outlet side end portion of the cylindrical exterior member, respectively, wherein an extended portion of the inlet side flange portion and an extended portion of the outlet side flange portion are fitted into an extended portion of the inlet side fitting groove and an extended portion of the outlet side fitting groove, the inlet side flange portion and its extended portion forming together an annular shape and the outlet side flange portion and its extended portion forming together a rectangular annular shape, and wherein one of the cylindrical exterior member and the interior member is made of rubber, and the other is made of resin. a cylindrical exterior member forming an outer perimeter portion of each of the air-fuel mixture passage and the air passage; and an interior member dividing an inside of the cylindrical exterior member into the air-fuel mixture passage and the air passage, wherein the interior member is attached to the inside of the cylindrical exterior member with use of elastic deformation of the interior member or of the cylindrical exterior member characterized in that the interior member has a tubular portion forming one of the air-fuel mixture passage and the air passage inside the cylindrical exterior member, an inlet side flange portion provided on an inlet side of the tubular portion, and an outlet side flange portion provided on an outlet side of the tubular portion, a portion between the inlet side flange portion and the outlet side flange portion of the tubular portion faces and contacts an inner perimeter surface of the cylindrical exterior member, and an inlet side fitting groove and an outlet side fitting groove into which the inlet side flange portion and the outlet side flange portion are fitted, respectively, are formed on an inlet side end portion and an outlet side end portion of the cylindrical exterior member, respectively, wherein an extended portion of the inlet side flange portion and an extended portion of the outlet side flange portion are fitted into an extended portion of the inlet side fitting groove and an extended portion of the outlet side fitting groove, the inlet side flange portion and its extended portion forming together an annular shape and the outlet side flange portion and its extended portion forming together a rectangular annular shape, and wherein one of the cylindrical exterior member and the interior member is made of rubber, and the other is made of resin.