Objective To explore the potential categories and influencing factors of care dependency developmental trajectory in elderly patients with comorbidities undergoing elective surgery. Methods A total of 598 elderly patients with comorbidities undergoing elective surgery from 5 general tertiary hospitals in Jiangsu Province were selected, then they were investigated utilizing the general data questionnaire, Cumulative Illness Rating Scale and Care Dependency Scale at 3 days after surgery (T1), at discharge (T2) and 1 week after discharge (T3).And the data were analyzed using the latent growth mixture model and disordered multi-classification logistic regression. Results The cumulative illness score of the participant was 14(8,17).The care dependency score at T1, T2 and T3 was (45.06±16.03) points, (54.40±16.32) points, and (63.37±10.91) points respectively, the developmental trajectory of patient care dependency was divided into independence steadily increasing group (36.3%), first decreasing and then increasing group (20.9%), rapidly increasing group (28.4%), first increasing and then decreasing group (14.4%).Multiple regression analysis showed that, patient age, educational background, personal monthly income, living style, whether the first onset and comorbidity degree affected the developmental trajectory of care dependency (P＜0.05 for all). Conclusion There are heterogeneous tra-jectories of care dependency in elderly patients with comorbid surgery.Medical staff should develop targeted nursing intervention according to different trajectories, so as to reduce care dependency.