An optical freeform surface has been recognized as a revolutionary element in a modern optical system because of its powerful ability of simultaneous aberration correction and structural optimization. However, the complex shape of its surface brings enormous difficulties and challenges to the precise measurement, which limits its manufacture level and has been one of the bottlenecks of its broad applications. Currently, the main measurement methods of an optical freeform surface are mainly developed from the ideas of aspheric measurement technologies. In this paper, we reviewed the development of the optical freeform surface measurement methods, especially focused on several typical measurement methods and their characteristics, and looked forward to the development trend of freeform surface measurement in future.