Abstract: Objective To introduce a case with 40-year chronic urticaria history, which was resolved after resection of invasive ductal breast carcinoma. Methods A patient with diffuse and refractory urticaria was diagnosed and treated in Beijing Shijitan Hospital affiliated to Capital Medical University on Dec.2 2014. Medical record was retrospectively investigated and the related literatures were reviewed. Results The patient was a 65-year-old female, who had been suffering from repeated diffused wheals for more than 40 years, and been aggravating for 4 years. She also had cough and wheeze for 1 year. Allergen tests showed that the patient was allergic to dermatophagoid mite, milk, peanut, wheat and shrimp. Diagnoses including chronic urticaria, bronchial asthma, occupying lesion of left breast, food anaphylaxis, hyperlipidemia and degenerative osteoarthropathy were established. Treatment was scheduled as avoiding wheat, shrimp, milk and peanut intake, and keeping food diary. Recurrent rash appeared after 21 months therapy with antihistamine. Occupying lesion of left breast was found 5 years ago. Mammography revealed one lesion in the patient's left breast with the infiltration to adjacent glands. Breast tumor resection was carried out in other hospital, and the pathological result was invasive ductal carcinoma which was consistent with the finding of mammography. Urticaria lesions disappeared after 2-cycles chemotherapy, without food taboos. Conclusion Breast cancer may contribute to the acute episode of chronic urticaria to a certain extent.