Abstract: Xihepu formation ( mtocene) of Kokeya condensate field can be divided into two members, upper member and lower one . The form er , indicated as X₄²—X₅²， sequenel , is a secondary oil-gas condensate reservoir with edge water and oil-ring gas cap . During the production, it is recognized that there were three periods of the reservoir pressure , i . e , stable , fall -off and build-up periods. The change inpressure gradient was evidently controlled by its edge water horizon tally or vertically. Belonging to fluvial： sedimentary facies , this reservoir is characterized by serious heterogeneities with permeability changing from higher for the lower to lower for the upper，and the horizontal higher than the vertical. However， no cross flow occurred between zones. The effect of the edge water and gas cap on the properties of its oil-gas condensate has been variable d uring the period of production and，with increase of oil-gas ratio, the content of condensate was reduced generally.