As of the census estimates GR2 of 2005, there were 331,310 people, 166,012 households, and 72,566 families residing in the city. The population density was 1,498.0/km˛ (3,879.8.0/mi˛). There were 166,012 housing units at an average density of 822.1/km˛ (2,129.2/mi˛). The racial makeup of the city was 52.97% White, 42.92% Black or African American, 0.21% Native American, 1.55% Asian, 0.04% Pacific Islander, 0.63% from other races, and 1.68% from two or more races. 1.28% of the population were Hispanic or Latino of any race.

There were 148,095 households out of which 25.1% had children under the age of 18 living with them, 26.6% were married couples living together, 18.6% had a female householder with no husband present, and 51.0% were non-families. 42.8% of all households were made up of individuals and 11.1% had someone living alone who was 65 years of age or older. The average household size was 2.15 and the average family size was 3.02.

The age distribution is 24.5% under the age of 18, 12.9% from 18 to 24, 31.6% from 25 to 44, 18.7% from 45 to 64, and 12.3% who were 65 years of age or older. The median age was 32 years. For every 100 females there were 89.4 males. For every 100 females age 18 and over, there were 85.6 males.

The median income for a household in the city was $29,493, and the median income for a family was $37,543. Males had a median income of $33,063 versus $26,946 for females. The per capita income for the city was $19,962. About 18.2% of families and 21.9% of the population were below the poverty line, including 32.0% of those under age 18 and 14.8% of those age 65 or over.

There has been concerted effort by the local government to stem the tide of emigrants. The population of Cincinnati decreased by nine percent between 1990 and 2000. Many of those leaving are living in the suburbs just outside of Cincinnati (often considered "Greater Cincinnati"). Several reasons are mentioned for this phenomenon common to many American cities, including job opportunities, entertainment, racial tensions, education opportunities and others. But according to a report released in The Cincinnati Enquirer on October 30, 2006, for the first time in over half a century, the U.S. Census Bureau has reported that the City of Cincinnati has actually gained population.[6] Based on the new 2005 estimate of just over 331,000, this represents an increase of nearly 20,000 new residents since 2004.