Introduction: Breast milk provides the ideal nutrition for infant
and it is more easily digested than infant formula. The main
aim of this study is to determine breastfeeding status, exclusive
breastfeeding, and their relation with mother’s age among
under-five children in the north of Iran. Material and Methods:
This was a descriptive, cross-sectional study, which was carried
out in 1997 persons (535 = Fars-native, 773 = Turkman and 689
= Sisstani) from 20 villages in the north of Iran. The calculated
sample sizes of 1800 respondents at least were needed for a
95% confidence and a maximum marginal error 0.02. Exclusive
Breastfeeding Duration (EBFD) and Breastfeeding Duration
(BFD) were classified based on WHO definitions. Results: BFD
is 20.16 months and statistical difference is significant among
three ethnic groups (p=0.001). Post hoc test are significant
between Fars-native and Turkman (p=0.001), and between
Turkman and Sisstani (p=0.002) and between Fars-native and
Sisstani (p=0.024). EBFD is 5.77 months and statistical difference
is significant among three ethnic groups (p=0.011). Post hoc test
is significant between Turkman and Sisstani (p=0.027). As whole,
duration of breastfeeding positively increased with mother’s age
(p=0.002) but statistical association was not significant between
exclusive breastfeeding duration and mother’s age. Conclusion:
In rural area in the north of Iran, the EBFD and BFD were 5.74
and 20.16 months, respectively and they were in Turkman group
more than in others. Mother’s age have a rising role for EBFD
and BFD whereas in all of ethnic groups it was not the same.