Microresonator frequency comb (MFC) is a tool for frequency measurement with high precision and integration potential. It will play a great role in deep space exploration and precise metrology. In this paper, the nonlinear optical generation and the device development of MFC are introduced. Especially, the status of application development of MFC including optical clock, range measurement, spectroscopy, optical-frequency synthesizer, low noise photonic microwave synthesis and coherent communication are elaborated. The future research hotspots and application prospects of optical frequency comb are predicted, which may promote the application development of optical frequency comb in metrology, measurement and communications.