Method and system for determining oil well crude oil cumulative yield by adopting stable daily yield

The invention provides a method and system for determining the accumulated yield of crude oil in an oil well by adopting stable daily yield. The method comprises the following steps: extracting petroleum in a target oil reservoir; measuring and determining the initial stable daily output q0 of the stable production period before linear decreasing production of the oil well and the stable daily output q1 of the first day of linear decreasing production based on the produced oil, and obtaining the accumulated output No of crude oil before linear decreasing production of the oil well; calculatingto obtain an initial daily decline rate Ddi; determining the stable daily output qt from the oil well decreasing production to the tth day and the relationship between the decreasing production timet and the decreasing period k month l y; obtaining the crude oil cumulative yield Nt in the linear decreasing period; and calculating to obtain the oil well crude oil cumulative yield Np. The method provided by the invention c