Background There is a complex causal framework for one-month to five-year-old child mortality. Hence, the improvement of this health indicator would also be quite gradual. This study was carried out to evaluate potential risk factors for death among children aged 1–59 months.

Method A nested case-control study was conducted in rural areas of Shahroud, in the central region of Iran. We selected 65 child deaths from the 2000–2008 birth cohort of 10 912 living newborns. A risk set sampling method was used to select controls (Case-Control ratio 1:2) who matched the cases in terms of age. The data were analysed using univariate and multivariate conditional logistic regression methods.

Results Significant associations with mortality were seen for: breastfeeding (OR 0.86, 95% CI 0.79 to 0.93, p<0.001), number of child cares (OR 0.90, 95% CI 0.83 to 0.98, p=0.017) and low birth weight (OR 7.38, 95% CI 1.38 to 39.58, p=0.020).

Conclusion Incomplete breast feeding duration, insufficient number of child cares and low birth weight are important risk factors for 1–59 month child mortality in Iran. It appears that complex and multiple factors are involved in mortality of under-5-year-old children, so combined efforts will need to be applied to improve child health.