Port St. Lucie is a city in St. Lucie County, Florida, United States. The population of Port St. Lucie was 88,769 at the 2000 census. According to the 2006 Census estimates, the city proper had an estimated population of 144,159.  Recent estimates from the St. Lucie County of Commerce has the population of the city over 150,000. . As of 2005, Port St. Lucie Metropolitan Area Population was 381,033.
As of the censusGR2 of 2000, there were 88,769 people, 33,909 households, and 25,736 families residing in the city. The population density was 453.7/km² (1,175.1/mi²). There were 36,785 housing units at an average density of 188.0/km² (487.0/mi²). The racial makeup of the city was 87.88% White, 7.09% African American, 1.24% Asian, 0.23% Native American, 0.03% Pacific Islander, 1.77% from other races, and 1.76% from two or more races. Hispanic or Latino of any race were 7.52% of the population.
There were 33,909 households out of which 31.6% had children under the age of 18 living with them, 61.8% were married couples living together, 10.0% had a female householder with no husband present, and 24.1% were non-families. 18.2% of all households were made up of individuals and 8.9% had someone living alone who was 65 years of age or older. The average household size was 2.60 and the average family size was 2.94.
In the city the population was spread out with 24.3% under the age of 18, 5.9% from 18 to 24, 28.1% from 25 to 44, 22.8% from 45 to 64, and 18.8% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 94.5 males. For every 100 females age 18 and over, there were 91.4 males.
The median income for a household in the city was $18,509, and the median income for a family was $19,162. Males had a median income of $18,730 versus $16,702 for females. The per capita income for the city was $18,059. About 15.7% of families and 17.9% of the population were below the poverty line, including 11.1% of those under age 18 and 9.8% of those age 65 or over.