This paper aims at locating the vein patterns in finger vein images with the help of fuzzy rule-based system. This system employs fuzzy reasoning that includes some linguistic variables which can be used effectively for extracting vein patterns from finger vein images. In this paper, the vein patterns in a finger vein image are traced using a Mamdani-type fuzzy rule base. A score-based matching is performed using minutiae features that are extracted with crossing number technique. Extensive experiments and comparative analysis conducted using the standard database from Hong Kong Polytechnic University shows that the vein pattern extraction by the proposed method gives better results compared to the conventional methods and error rates are much lesser than existing techniques. The efficient and accurate vein pattern extraction using the proposed method aids in faster vein matching and authentication in the case of finger vein biometric. © Springer Nature Singapore Pte Ltd 2019.