In this paper, the ultrafiltration in separation of biological enzymes was reviewed, including the principle of ultrafiltration technology, separation process as well as the effects of fermentation broth properties, ultrafiltration membranes and ultrafiltration conditions on the ultrafiltration performance of biological enzymes. Meanwhile, the recent achievements in improving the ultrafiltration performance were summarized and discussed in three aspects of fermentation liquid treatment, ultrafiltration membranes and ultrafiltration process optimization. Finally, it is considered that the future development directions of biological enzymes ultrafiltration technology are as follows: the development of ultrafiltration mathematical models; the improvement of enzyme stability; the improvement and development of ultrafiltration membranes; the improvement of ultrafiltration technology.