Abstract: Through the physical simulation experiment,study lamellate low-grade reservoir starting pressure grade rule,analyse the relations between layer physical property and flow coefficient,compare the difference of the single-phase starting pressure grade and two-phase starting pressure grade,study the starting pressure grade effect rules to the single well productivity and limit injection/production well space and propose the corresponding technical countermeasures. The result indicated that we should study the starting pressure grade rule in lamellate low grade reservoir,choose the appropriate injection/production pressure differential, and establish the effective displacement differential pressure to improve development effect.