Women diagnosed with breast cancer may have serious psychological problems and will suffer from adjustment disorder (AjD). We investigated the prevalence of AjD in female breast cancer patients who were diagnosed within 1 year and examined the severe life events they experienced, and the most common symptoms of AjD. 342 newly diagnosed (<1 year) female breast cancer patients were recruited from Tongji Hospital and Hubei Cancer Hospital in Hubei, China, from July 2018 to May 2019. The patients completed the self-report questionnaire including demographic characteristics and the scale ADNM-20 for the diagnosis of AjD. SPSS20.0 was used for data analysis. As a result, the prevalence of AjD in breast cancer patients was 38.6%. Patients from rural areas and lacking of exercise were more likely to suffer from AjD (P<0.05). The prevalence of AjD in patients who did not regard breast cancer as the most severe life event was higher than that in patients who took breast cancer as the most severe life event (44.4% vs. 33.9%, P<0.05; OR=1.728, 95% CI=1.072-2.787). The symptom that scored highest was preoccupation (3.15). We found that the prevalence of AjD in women with breast cancer in this study is very high and warrants more attention. Patients from rural areas, lacking of exercise and subject to multiple stressors are more likely to suffer from AjD. The commonest and severe symptom is preoccupation.