To provide a heated cylinder for resin melting in a molding machine which realizes high material supply/transport performance, cost reduction, and more favorable maintenance performance, while making the plan view/plan sectional view shape of a resin charging port into a circular shape. The resin charging port of the heated cylinder is formed to include: an upper charging path section formed in a circular shape in a plan sectional view; a lower charging path section which is formed in a square shape or oblong hole shape in a plan sectional view; and an intermediate charging path section which smoothly links an inner surface of the upper charging path section and an inner surface of the lower charging path section.