The growth and delamination mechanism of cubic boron nitride (c-BN) film on silicon substrate was investigated with Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM), c-BN films were prepared by the helicon wave plasma chemical vapor deposition process on (100) Si. The film deposited under the intense impact of energetic ions is usually delaminated from the substrate after deposition. It is found that moisture in the air, as well as severe compressive stress in the film, contribute to him delamination. From FTIR and TEM characterization, a model for the delamination mechanism of c-BN film is suggested. Based on the delamination mechanism, several kinds of remedies such as post-annealing and post-N-2 plasma treatment were carried out to improve the adhesion. The effects of these respective remedies on the adhesion of c-BN film are also discussed.