Objective: To investigate the clinicopathologic characteristics of breast cancer in women under 35 years of age. Methods: The clinical and pathological data of 85 young women (under 35 years of age) with breast cancer (observational group) admitted from 2005 to 2010 were retrospectively analyzed, and were compared with those from 164 middle-aged and elderly women with breast cancer (control group), who were admitted during the same period and randomly selected. Results: In the 85 young breast cancer women in observational group, there were no specific clinical symptoms, the misdiagnosis rate was 45.88%, average age was (30.27±2.41) years and average disease course was (11.51±1.56) months. Compared with control group, observational group showed larger tumor size, more advanced clinical stage, and poorer differentiation in histological grade (all P<0.05), but no statistical difference in constitution of the pathological types (P>0.05). In addition, the expression levels of estrogen receptor (ER) and progesterone receptor (PR) were lower but c-erbB-2 protein expression level was higher in the breast cancer tissues in observational group than those in control group (all P<0.05), and both rate and number of axillary lymph node metastasis in observational group were higher than those in control group (both P<0.05). Conclusion: Breast cancer in young women has distinct clinicopathologic characteristics and molecular biological features. Early diagnosis and treatment is the effective way to improve the survival rate in these patients.