The resampling of the passband signal with variable frequency is likely implemented by interpolating and decimating the original sequence according to the converting ratio (P/Q). When the value of P is very large, the multiple interpolating filters will be required, and due to anti-image frequency filtering, the coefficient matrix of filters are very complex, which results in the resampling difficult to implement. This paper presents a method of the Polynomical Approximate Filtering (PAF). It uses a group of coefficient matrixed for low-order PAF, with efficient operation and variable interpolating delay. The computer simulation show that it is suitable to the high order interpolating filters with variable delay. In some cases, the tolerance is within the allowable range.