Abstract: Objective: To investigate the effects of IMR, iDose<sup<4</sup< and FBP reconstruction algorithms on the image quality of multi-row spiral CT in the chest before costal cartilage rhinoplasty. Methods: A total of 60 patients who met the inclusion criteria and planned to receive autogenous costal cartilage rhinoplasty were collected. All patients underwent chest CT examination before operation and completed relevant 3D reconstruction based on images generated by IMR, iDose<sup<4</sup< and FBP reconstruction algorithms, and the image quality of the three reconstruction algorithms was analyzed. The subjective evaluation score and objective evaluation indexes of image quality in each group were recorded and compared including costal cartilage CT value, noise, signal-to-noise ratio and contrast noise ratio. Results: The CT reconstruction images obtained by the three algorithms could all accurately assess the degree of costal cartilage calcification. Subjective evaluation of image quality showed that the IMR group obtained higher score and held obvious advantages, mainly reflected in the IMR reconstruction algorithm compared with iDose<sup<4</sup< and FBP two algorithms in the costal cartilage calcification spot edge display and inhibition of liver, gastrointestinal content and weakened heart beating artifacts. Objective evaluation of costal cartilage CT value, SNR, contrast noise ratio and statistical analysis, the final statistical results showed that IMR, iDose<sup<4</sup< and FBP reconstruction algorithm group showed significant statistical differences, IMR group showed obviously the best image quality. Conclusion: All three reconstruction algorithms of IMR, idose<sup<4</sup< and FBP can accurately evaluate the presence and degree of calcification of autologous costal cartilage. Under the same scanning conditions, compared with the reconstruction algorithms of FBP and iDose<sup<4</sup<, IMR reconstruction algorithms can reducecan significantly reduce image noise, improve CNR and SNR, and improve the subjective image quality of costal cartilage. It is more acceptable to clinical surgeons and can be used as the preferred algorithm reconstruction technique for costal cartilage CT examination, which is most worthy of promotion.