The invention provides a mobile terminal unlocking method and a mobile terminal unlocking device. The method includes: acquiring a fingerprint of a user, and determining quantity of fingerprint feature points, matched with pre-stored fingerprint feature points, in the fingerprint; judging whether the quantity of the fingerprint feature points is smaller than a first preset quantity threshold or not, if the quantity of the fingerprint feature points is smaller than the first preset quantity threshold, judging whether the quantity of the fingerprint feature points is larger than a second preset quantity threshold or not, and if the quantity of the fingerprint feature points is larger than the second preset quantity threshold, acquiring feature points of other body signs except for the fingerprint of the user; judging whether the feature points of the other body signs meet preset conditions or not; if the preset conditions are met, judging whether the quantity of the feature points of the other body signs is larger than or equal to a third quantity threshold, and if yes, unlocking the mobile terminal. The mobile terminal unlocking method and the mobile terminal unlocking device have advantages that fingerprint unlocking of a mobile terminal is realized without reduction in safety, and user experience in fingerprint unlocking is improved.