Abstract: Zhoufan Salt Basin develops complex salt rhythmic strata. Density should identify the sand reservoir in this area. Unfortunately, the density difference between sand and other lithology is very small, which causes the traditional pre-stack inversion method that based on Aki-Richards equation cannot satisfy the reservoir prediction task. We substitute the Zoeppritz equation into general inversion frame and then deduct prestack wide-angle inversion formula. Our inversion formula overcomes the weakness of Aki-Richards equation which cannot apply the wide angle information accurately. In this case, the inversion accuracy is improved. The synthetic test and field data application illustrate that our density inversion result is more accurate than the traditional one and satisfy the reservoir prediction in Zhoufan Salt Basin.