Objective: This study primarily focuses on analyzing the inductive effects of emotional disturbances on the malignant transformation process of mammary gland epithelial cells. Methods: A total of 42 patients with malignant transformation of mammary gland epithelial cells (breast cancer, observation group) and 42 patients without malignant transformation of mammary gland epithelial cells (non-breast tumors, control group) were selected as research subjects. The earliest consultation time was January 2022, and the latest was January 2024. The extent of psychological stress impact on these patients was compared. Results: Compared with the control group, the observation group experienced a higher frequency and intensity (LEU value) of adverse life events, with P < 0.05. The intensity of adverse life events in the observation group, except for mild events, was significantly higher than that in the control group (P < 0.05). In terms of the content distribution of adverse life events, the proportion of marital and family problems in the observation group was significantly higher than that in the control group (P < 0.05). The negative coping score and positive coping score in the observation group were significantly different from those in the control group (P < 0.05). Regarding social support, the objective support score in the observation group was higher than that in the control group (P < 0.05). Conclusion: During the malignant transformation process of mammary gland epithelial cells, long-term emotional disturbances have a significant impact, indicating a close relationship between psychological stress and the occurrence of breast cancer.