Imaging spectrometers, which collect data over three dimension-two spatial and one spectral so that a complete dataset is typically referred to as a datacube, is one of the most powerful and widely used characterization tools in accurate mapping of wide areas remote sensing, object identification and recognition, environment assessment and management, clinical diagnosis imaging and process monitoring and control. According to the different spectral principle and component, imaging spectrometers were divided into four classes as filtering imaging spectrometers, dispersive imaging spectrometers, interferometric imaging spectrometers and snapshot imaging spectrometers. A comprehensive review of main representative forms and applications of various imaging spectrometers on the basis of classification was provided, and the possible development and application of imaging spectrometers in the future were prospected.