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Purpose: X-ray scatter poses a significant limitation to image quality in cone-beam CT(CBCT),as well as beam hardening,resulting in image artifacts,contrast reduction,and lack of CT number accuracy.Meanwhile the x-ray radiation dose is also non-ignorable.However most of scatter or beam hardening correction methods are independently developed,and rarely combined with low-dose CT reconstruction.In this paper,we combine scatter suppression with beam hardening correction for sparse-view CT reconstruction to improve CT image quality and reduce CT radiation.Methods: Firstly,scatter fluence is subtracted from the measured total fluence at detector to suppress scatter artifacts.Assuming that signal in the blocker shadow is only attributable to x-ray scatter,the 2D scatter distribution is estimated by interpolating pixel values measured along the top and bottom peripheries of the detector behind the lead blockers.After scatter subtraction,beam hardening correction is then implemented.As beam hardening is caused by x-ray spectrum polychromatism,the attenuation coefficient at different energies is modeled and estimated as an equivalent attenuation coefficient at the effective energy,and integrated into the forward projector of the algebraic reconstruction technique(ART).Finally the CS-based iterative reconstruction is carried out for sparse-view CT reconstruction to reduce the CT radiation.Results: Preliminary validation using Monte Carlo simulated HA phantom indicates that with only about 25%of conventional dose,our method reduces the magnitude of cupping artifact by a factor of 6.1,increases the contrast by a factor of 1.4 and the CNR by a factor of 15.Conclusion: The proposed method can provide good reconstructed image with few-view CT,with effective suppression of artifacts caused by scatter and beam hardening,as well as decreasing the radiation dose.With this proposed framework and modeling,it may provide a new way for low-dose CT imaging.