Abstract: Whether simulation resukts represent actual reservoir performance this depennds on whether reservoir deseriptionand reservoit simulation model selection are right and reilabie. while the eritical points of reservoir description are determination of the perameters of oilfield geslogy, reservoir rock properties and formation fluid properties. Base on application this paper discusses simulation model selection and grid system selection for the black oil reservoirs, and gives application limit and function for each model. This paper also presents the required data and some data ureatment methods for biack oil reservoir simulation study. The major aim of this work is in order to mester perfectly reservoir simulation techniqes and to solve validly practical reservoir engineering problems.

Key words: Black oil Reserroirs, simulation model, grid system, reservoir description