The invention relates to the technical field of computed tomography (CT), in particular to a CT imaging method. The CT imaging method comprises the following steps: performing full-dose scanning before interventional therapy and reconstructing to obtain a full-dose image; after the interventional therapy begins, partially scanning a region of interest (ROI) comprising needle point position and reconstructing to obtain an ROI image; and merging the full-dose image and the ROI image. By the CT imaging method, the ROI is partially scanned after the interventional therapy begins, so the radiation dose is greatly reduced compared with full-dose scanning adopted in the prior art.