Abstract: Because of the high inhomogeneity and bad property of CⅢ1st reservoir in Donghe oilfeild of the Tarim basin, the water injection is usually inaccessible to the geology injection allocation. So the producing energy is deficient and the oil production descends quickly. The conventional acidification can't relieve the formation deep contamination. According to the trait of the low permeability and high component kaolinite clay, this paper developed a multi-hydro acid system that can realize the deep acidification slowly, and analyzed the adaptability of multi-hydro acid applied in Donghe oilfield combined with the acidification mechanism of it. According to the trait of high inhomogeneity, hydrotrop was diverted into the acidizing fluid, and the simulated experiment of diversion acidification was carried out for site core in laboratory. The multi-hydro acid was recommended to apply in A15H well in this reservoir and significant effect of increasing injection was attained.