Multi-frame image super-resolution method fuses the information of multi-frame low-resolution images to reconstruct high-resolution images. For multi-frame image super-resolution, the accurate estimation of blur kernel of low-resolution image is prerequisite for efficiency information fusion. Traditional super-resolution method usually assumes a known blur kernel and uses the Gaussian filter blur kernel for the enhancement. It also needs to tune the parameters by time-consuming hand-tuning. The proposed method acquires the super-resolution method based on the variational Bayesian method. The high-resolution image, the blur kernel and the model parameters are estimated simultaneously and automatically in the optimal stochastic sense. Experiments and simulations demonstrate that the proposed blind super-resolution method based on blur kernel self-adaptive estimation outperforms the state-of-art super-resolution method in variational Bayesian framework, especially, for the high signal to noise ratio scenarios.