BACKGROUND: Inappropriate feeding and hygiene practices and poor environment are associated with malnutrition. We aimed to investigate the contributions of feeding, hygiene practices and recent illness to the nutritional status of rural Cambodian infants and any sex-specific differences. METHODS: In a cross-sectional study, nested within an ongoing birth cohort, trained fieldworkers conducted anthropometry and collected information from the main caregiver during home visits. Multivariable linear regression was used to investigate associations with nutritional status as length-for-age z-scores (LAZ) and weight-for-length z-scores (WLZ). RESULTS: A total of 156 children, 87 (55.8%) male, ages 0-11 months were enrolled. The prevalence of acute malnutrition (WLZ <-2) in males and females was 2.3% (2/87) and 5.8% (4/69), respectively, and 23.0% (20/87) of males and 14.5% (10/69) of females were stunted (LAZ <-2). WLZ but not LAZ decreased with age. WLZ was independently negatively associated with increasing age (β-coefficient -0.14 [95% confidence interval {CI} -0.20 to -0.08], p<0.001), and regular use of feeding bottles (β-coefficient -0.46 [95% CI -0.83 to -0.10], p=0.014), and positively with handwashing with soap (β-coefficient 0.40 [95% CI 0.05 to 0.75), p=0.027). CONCLUSIONS: The prevalence of acute malnutrition was low, but stunting was prevalent without evidence of a sex difference. Non-linear growth faltering was associated with increasing age and hygiene/feeding practices.