Taper end-mills are widely used in CNC machining and the flute are crucial to the cutting performance of the end-mill. However, it is very difficult to form the wheel path of grinding taper end-mill due to its complex structure and variable cross-section. In the traditional methods, the wheel path is generated by experience, and the accuracy of flute parameters cannot be guaranteed. To overcome those problems, this paper proposed a wheel path generation approach for taper end-mills flute-grinding subject to adaptive cross-section, which is capable to ensure the accuracy of parameters of variable cross-section. In the wheel path generation, the taper end-mill is discretized into a series of finite slices, which can be transformed into solving a series sub-problem of grinding cylindrical end-mills. To eliminate the interference and discontinuity caused by the discretization, the enhancement based on sensitivity analysis and smoothing method are used to optimize the grinding wheel path. Finally, the approach is validated by both simulation and experiments. The results indicated that this approach is capable to generate the wheel path for grinding the taper end-mill flute accurately and efficiently subject to the adaptive cross-section parameters.