An apparatus and method of segmenting sensor data are provided. The apparatus includes a sensor, a first segmentation unit, a continuity evaluation unit, a second segmentation unit, and a segmentation determination unit. The sensor collects sensor data for a process of the semiconductor manufacturing facility. The first segmentation unit extracts a variation point of the sensor data to perform an abnormal difference (AD) segmentation on the sensor data based on the at least one variation point. The continuity evaluation unit evaluates a continuity ratio of the sensor data. The second segmentation unit performs a free-knot spline (FS) segmentation on the sensor data when the continuity ratio exceeds a reference ratio. The segmentation determination unit compares the AD segmentation result with the FS segmentation result and to select one of the results on the comparison result.