PROBLEM TO BE SOLVED: To provide a non-contact flow measurement system using a Doppler sensor capable of easily obtaining an instantaneous flow.SOLUTION: A non-contact flow measurement system 100 using a Doppler sensor 1 for measuring a flow of a fluid discharged from a discharge port with the Doppler sensor 1, includes: storage means that stores a Doppler shift component obtained from the Doppler sensor 1 as digital data by sequential analog-to-digital conversion with an A/D converter； zero-cross detection means that detects the number of zero crosses from a Doppler shift component amount of the digital data； zero-cross number counting means that counts the number of zero crosses for each fixed interval； and a flow conversion table that converts the flow into a predetermined instantaneous flow in accordance with the number of zero crosses of the zero-cross number counting means.
