Objective To explore the status and factors associated with fatigue in the puerperium in women of advanced maternal age, and to provide reference for targeted intervention.Methods A convenience sample of 353 women aged 35 years or older were selec-ted from 3 hospitals in Tangshan when they visited the hospital for a regular 6-week postpartum check-up.They were invited to fill out the Postpartum Fatigue Scale, the Psychological Capital Questionnaire, the Family APGAR Index and the Pittsburgh Sleep Quality Index.Factors influencing postpartum fatigue were determined by using random forest algorithm and LASSO regression.Results The total score of fatigue was （15.29±2.81） and the incidence of fatigue was 90.9%.Psychological capital, the volume of postpartum blood loss, BMI, pregnancy complications and sleep quality were the influencing factors of postpartum fatigue in women of advanced maternal age （all P＜0.05）, which could explain 44.7% of the total variance.Conclusion The level of postpartum fatigue in women of advanced maternal age is high, and those with higher BMI and pregnancy complications should be paid more attention.In order to reduce postpartum fatigue, medical staff should enhance psychological capital of the puerpera, decrease postpartum hemorrhage, and improve their sleep quality.