Milroy is located along Minnesota Highway 68.
There were 119 households out of which 28.6% had children under the age of 18 living with them, 45.4% were married couples living together, 12.6% had a female householder with no husband present, and 36.1% were non-families. 33.6% of all households were made up of individuals and 11.8% had someone living alone who was 65 years of age or older. The average household size was 2.28 and the average family size was 2.87.
In the city the population was spread out with 26.9% under the age of 18, 6.3% from 18 to 24, 26.2% from 25 to 44, 23.2% from 45 to 64, and 17.3% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 122.1 males. For every 100 females age 18 and over, there were 104.1 males.
The median income for a household in the city was $33,625, and the median income for a family was $36,042. Males had a median income of $29,722 versus $18,750 for females. The per capita income for the city was $16,866. About 5.2% of families and 9.3% of the population were below the poverty line, including 22.4% of those under the age of eighteen and none of those sixty five or over.