Purpose: This study aimed to explore the levels of postpartum fatigue, parenting stress, family support, and postpartum depression (PPD) experienced by first-time Chinese mothers and to investigate their impact on PPD. Methods: This cross-sectional survey involved 150 primigravida women attending postnatal checkups in Hebi City, Henan Province, China. Demographic data and information on environmental variables (living conditions, family relationships), postpartum fatigue, parenting stress, family support (expected vs. actual level), and PPD were collected. Results: The average age of the women was 26.25 years (SD, ±3.90), with 78.7% at risk for PPD (score ≥10). Significant correlations were found between PPD and postpartum fatigue (r=.63, p<.001), parenting stress (r=.59, p<.001), and family support (r=.40, p<.001). In model 1, which examined the influence of women's demographic variables on PPD, significant factors included a poor relationship with parents (β=.24, p=.001), a poor relationship with parents-in-law (β=.18, p=.029), and a poor relationship with the husband (β=.20, p=.013). When the three research variables were incorporated into model 2, the factors contributing to a higher level of PPD included a poor relationship with parents-in-law (β=.14, p=.033), increased postpartum fatigue (β=.37, p<.001), increased parenting stress (β=.33, p<.001), and less family support than expected (β=.12, p=.048). Conclusion: The most critical factors influencing PPD include postpartum fatigue, parenting stress, poor relationships with parents-in-law, and low family support among Chinese primiparas. To mitigate PPD levels, healthcare professionals should screen mothers for depression in outpatient clinics and offer education and counseling to both mothers and their families or companions regarding PPD.