The present disclosure provides a system and method for X-ray imaging. The method of calculating scatter in an X-ray image may include forming a modulated X-ray image. The method of forming the modulated X-ray image may include acquiring X-rays through a collimator module and an imaged object in sequence to generate an X-ray image group； the acquisition may be performed during a movement of the collimator module in a first direction and the X-ray image group may include a plurality of X-ray images acquired at different times during the movement of the collimator； extracting sub-zones from the plurality of X-ray images in the X-ray image group； combining the sub-zones in the first direction to form the modulated X-ray image. In the present disclosure, an intensity distribution of the X-rays may be adjusted flexibly using a collimator without adding any extra hardware. In addition, scatter components in the X-ray images may be calculated to eliminate the scatter in the X-ray images finally.
