Methods of reconstructing a CT image and CT devices are provided in examples of the present disclosure. In one aspect, scanning parameters for a CT device is obtained to perform a scan on a subject, a target reference detector is determined from the reference detectors according to the scanning parameters； the scan is performed on the subject according to the scanning parameters to obtain detection data outputted by the detector and reference detection data outputted by the target reference detector； energy data of the original X-rays emitted by the bulb tube with the scanning parameters is determined according to the reference detection data outputted by the target reference detector； the detection data outputted by the detector is corrected based on the energy data of the original X-rays to obtain scanning data； and the CT image of the subject is reconstructed by performing image reconstruction based on the scanning data.
