Duddhi is a town in the Sonbhadra district of Uttar Pradesh.It is located between 24.22° North latitude and 83.25° East longitude at a height of 213 metres(698 feet) above mean sea level.

According to the 2001 census report, Duddhi had a population of 11,606 inhabitants. Males constitute 54% of the population while females constitute 46% of the population. In Duddhi, 17% of the population is less than six years of age. Duddhi has an average literacy rate of 67% which is higher than the national average literacy rate of 59.5%. The male literacy rate is 74% and, the female literacy rate is 58%.