Background: Breastfeeding after caesarean section is often delayed due to post-operative pain, limited mobility, and reduced mother infant contact. In addition to clinical factors, social norms especially support from husbands, family members, and healthcare providers can influence breastfeeding practices. This study examined the association between social norms and breastfeeding practices during the first three postpartum days among post-caesarean mothers in East Java, Indonesia. Methods: a cross-sectional observational study was conducted from July to October 2024 at a hospital in East Java. a total of 296 post-caesarean mothers were selected using simple random sampling. Data were collected through structured interviews and medical record reviews. Social norms were assessed using a Subjective Norm Scale adapted from the Theory of Planned Behavior, measuring perceived support from husbands, family members, and healthcare providers. Breastfeeding practices were evaluated daily from day 1 to day 3 postpartum using a composite Breastfeeding Practice Index based on WHO indicators. Descriptive statistics summarized participant characteristics. associations were analyzed using Chi-square tests, while changes across postpartum days were assessed using Cochran’s Q test, Friedman test, and post-hoc analyses. Results: high support was reported from husbands (68.2%), family members (62.8%), and healthcare providers (72.3%), while 66.9% of mothers had positive subjective norms. breastfeeding practices improved significantly from day 1 to day 3, with good practices increasing from 60.1% to 64.9% (Friedman test, p = 0.001). all individual breastfeeding indicators improved significantly (Cochran’s Q test, p < 0.05). social norms were significantly associated with breastfeeding practices; mothers receiving high support from husbands, family, and healthcare providers were more likely to practice good breastfeeding (p < 0.01). subjective norm scores were highest among mothers with good breastfeeding practices (p < 0.001).conclusion: early breastfeeding practices among post-caesarean mothers improve over time and are strongly influenced by social norms. strengthening support from husbands, family, and healthcare providers is essential to promote optimal breastfeeding after caesarean delivery.