Based on studying development, geochemical and generation gas characteristics  of  sourcerock and development, seal characteristics of caprock of deep strata in Xujiaweizi region. This paper studied the match relation between sourcerock and  caprocks in time and space and their controlling to farmation of gas reservoirs in this region. The time match relation between K₁d₂ or K₁q_1+2mudstone caprocks and K₁sh+ycsourcerock in Xujiaweizi region is good, but former is better than the latter. It is the important  cause that there is more gas distribution under K₁d₂ mudstone caprock than that under  K₁q_1+2 mudstone caprock. The space relation  between K₁d₂ orK₁q_1+2mudstone caprock and  K₁sh+yc  sourcerock is best in the centre of Xujiaweizi depression. This is  the important cause that gas distributes from basement rock to K₁q_1+2 in the three structures of Shengping, Wangjiatun and Changed in Xujiaweizi  depression.The quality matching relation between K₁d₂ caprock and  K₁sh+yc sourcerock is better than that between K₁q_1+2caprock and  K₁sh+yc   sourcerock. This is the another important cause that there is more gas distribution under  K₁d₂  caprock than that  under K₁q_1+2 caprock. The center of Xujiaweizi depression is the most favorable area for gas to accumulate and form gas reservoirs from the  matching relation between caprock and sourcerock.