Abstract: In allusion to the differences in gas demands for different gas users, which often change gas supplymode and operation scheme of gas pipeline, an investigation on gas demand law of upstream and/ordownstream gas users is made.It is considered that by means of determining pore diameterof orificeflowmeter, diagramming current offtake pipeline, determining the flow rate scope at different pressure, analyzing or choosing available gas supply mode, the operation scheme of gas pipeline can be effectivelyoptimized.