The invention provides a detection method and device used for detecting fingerprints. The method comprises the steps that S1, the fingerprint detection device comprises a detection electrode, and detects capacitance on the detection electrode; S2, when the capacitance exceeds a preset capacitance threshold value, some detection units of a fingerprint detection array are started for carrying out fingerprint pre-detection to obtain data information of fingerprint pre-detection; S3, when the data information exceeds a first preset threshold value, all the detection units of the fingerprint detection array are started for carrying out fingerprint scanning. According to the detection method used for detecting the fingerprints, after it is reliably and effectively identified that the fingers touch the fingerprint detection device, the fingerprint detection array is restarted for carrying out all-array fingerprint scanning, and therefore the power consumption of fingerprint detection is greatly reduced.