This study proposes a cascade-type fiber curvature sensor with bowknot-type taper and a tapered fiber structure based on intermodal interference. The proposed sensor comprises two bowknot-type tapers prepared by fiber fusion splicing using single-mode fibers, and the tapered structure is added by fixed-point tapering. Experimental results show that when the tapered structure has a pulling cone length of 0?2500 μm, the sensitivity of the sensor increases alongside the pulling cone length; furthermore, for pulling cone lengths of 3000 μm and 3500 μm, sensor sensitivity tends to be stable. The maximum sensitivity reaches -22.50 nm/m^-1 in a curvature range of 3.4072?6.0881 m^-1 for a pulling cone length of 2500 μm. This structure has both high sensitivity and high stability, which effectively solves the problem of temperature cross-sensitivity and simultaneously simplifies the sensor manufacturing process, improving its compactness and reducing the production cost.