Frame rate up conversion has been discussed for several years. Especially in the emerge of large-size LCD display devices, frame rate up conversion erase the motion blur caused by liquid crystal rotation. Among existing techniques, frame rate up conversion by motion compensation is more and more popular. In this paper, a novel frame rate up conversion method, overlapped block-based adaptive bilateral motion estimation, is proposed combining adaptive sum of bilateral absolute difference and overlapped block motion estimation. Based on the analysis of block size transition, smaller block size compensation is applied while the search block size is large. According to the experiment results, the proposed work outperforms existing work by 6.25 dB on average. This concludes a high video quality frame rate up converter design.