Abstract: This paper presents a composite deep profile control system of secondary crosslinking gels and polymer microspheres, aiming at the problems of water cut rising fast and ineffective or poor effective water circulation in Wen?8 block of Wenmi oilfield in Tuha basin. The organic chrome crosslinking agent is used as the first crosslinking gel, and the JQ?1 and FJ?1 phenolic composite crosslinking agent is selected as the second one. At 25℃ and after 5 hours, the first crosslinking gel’s viscosity is 374 mPa·s; at 78℃ and after 10 d, the secondary crosslinking gel’s viscosity reaches 17 005 mPa·s. The polymer microsphere is characterized by good anti?temperature and anti?salinity, and hydration time stability. At reservoir temperature of 78℃ and salinity of 40 000 mg/L, after 20 d, the expansion multiplying factor of it is 6.08. Compositing the secondary crosslinking gel system with SD?320 microspheres for profile control, the estimated resistance factor by core flow experiment is higher than 20, the residual resistance factor is bigger than 18, and the recovery factor is enhanced by 15.5%. It is concluded that this composite profile control system can not only prevent plugging agent from leaking, effectively, but also can fit the high reservoir temperature of 78℃, being of good application prospect in Wen?8 block of Wenmi oilfield