A new method of predistortion to improve the qualities of the wideband LFM‐CW signal generated by a hybrid DDS‐PLL generator is introduced. The purpose of the predistortion is to reduce the phase error in the output without any increasing of the complexity. A circuit is designed and realised to generate wideband LFM‐CW. With the predistortion, the maximum phase error is depressed to be less than 5°, and the PLSR of the compression with Hamming weighting is improved to be better than −37dB.