Objective To explore the mediating role of chronic illness resources and self-care behavior on disease perception and symptom distress in patients with breast cancer-related lymphoedema, and to provide a reference for conducting targeted nursing interventions to reduce their symptom distress. Methods A total of 415 outpatients with breast cancer-related lymphoedema were selected using convenience sampling method, then they were investigated by using a general information questionnaire,the Brief Illness Perception Questionnaire (B-IPQ), the Chronic Illness Resources Survey (CIRS), the Breast Cancer Related Lymphedema Self-care Scale (BCRL-SS), and the Breast Cancer and Lymphedema Symptom Experience Index (BCLE-SEI). Results The participants′ total score of BCLE-SEI was 75.14±21.38, which was positively correlated with the score of B-IPQ, and was negatively correlated with the score of CIRS and BCRL-SS (all P＜0.05). Chronic illness resources and self-care behavior played mediating role between disease perception and symptom distress, which accounted for 17.36% of the total effect. Conclusions The symptom distress in patients with breast cancer-related lymphoedema is at a medium and low level. Disease perception can directly affect symptom distress, and it can also indirectly affect symptom distress through the chain mediating effects of chronic illness resources and self-care behavior. Medical staff can alleviate the symptom distress of this population via reducing their negative disease perceptions,and improving their level of chronic disease resource and self-care behavior.