The invention relates to a non-linear fusion method for internal and external radiotherapy doses of a 
cervical cancer. The method comprises: obtaining internal and 
external irradiation radiotherapy CT images and internal and 
external irradiation radiotherapy dose distribution of a to-be-detected 
cervical cancer; on the basis of non-linear 
image registration, mapping the internal 
irradiation radiotherapy CT image to the 
external irradiation radiotherapy CT image to obtain a transformation relationship between the internal and external 
irradiation radiotherapy CT images of the to-be-detected 
cervical cancer; according to the transformation relationship between the internal and external 
irradiation radiotherapy CT images, transforming internal irradiation 
radiotherapy dose distribution into equivalent external irradiation 
radiotherapy dose distribution; and carrying out fusion of the equivalent external irradiation radiotherapy 
dose distribution and external irradiation radiotherapy 
dose distribution after transformation by 
image fusion, rebuilding a distribution curve of internal and external radiotherapy doses, and obtaining a total practically subjected 
dose of a 
tumor target region of the to-be-detected cervical 
cancer and surrounding organs at risks during the comprehensive internal and external irradiation radiotherapy process. The non-linear fusion method is applied to an image-guided 
radiation therapy of a cervical 
cancer, thereby improving accuracy of radiotherapy dose evaluation.