Abstract: In order to real-time get optical power signal transmitted in optical fiber，a new high-speed acquisition system is designed.Based on LabVIEW virtual instrument programming language and USB technique, the system combines an optical receiver with an USB DAQ card USB-M6251 of NI Company．It overcomes the disadvantages of the traditional system, such as low sampling rate，single channel display，insufficient man machine interface function and poor portability, and realizes the real-time acquisition，display and storage of optical-power signal in dual channels with sampling parameter controllable.Experiments prove that the optical power signal acquisition system is reliable and practical，and it provides a good man machine interface. It can be used to monitor the optical power signal in various optical fiber communication systems.