Based on the imaging process of pushbroom hyperspectral imager, a correction method for optic crosstalk was developed. An area that has white calibration target was selected as reference data. The target pixels crosstalk quantity was gained using the subtraction between the two lines of reference data, and it was fitted to restrain noise. Using recursion method, crosstalk quantity of single pixel was calculated from the fitted function, and it could be used to correct the optical crosstalk of the whole data. Three PHI (pushbroom hyperspectral imager) data which have different ground scene were corrected. It was showed that optical crosstalk in corrected data is lightened obviously, and the data quality is improved effectively in both the spectral dimension and spatial dimension. The spectral changing caused by optical crosstalk is also corrected, and the bands with definition increased more than 50% accounts for 83% of the total bands. Optic crosstalk is obtained form hyperspectral data itself which is independent of other data source. It is proved that the correction method is valid, and it is applicable for different ground type. The correction method also provides a way to measure the optic crosstalk of hyperspectral imager in the lab.