Big Bend is located at GR1.(41.019803, -121.907881)
As of the censusGR2 of 2000, there were 149 people, 70 households, and 38 families residing in the CDP. The population density was 10.1/km² (26.1/mi²). There were 106 housing units at an average density of 7.2/km² (18.5/mi²). The racial makeup of the CDP was 83.22% White, 8.72% Native American, 1.34% Asian, 3.36% from other races, and 3.36% from two or more races. Hispanic or Latino of any race were 3.36% of the population.
There were 70 households out of which 21.4% had children under the age of 18 living with them, 42.9% were married couples living together, 4.3% had a female householder with no husband present, and 45.7% were non-families. 41.4% of all households were made up of individuals and 12.9% had someone living alone who was 65 years of age or older. The average household size was 2.13 and the average family size was 2.97.
In the CDP the population was spread out with 23.5% under the age of 18, 4.7% from 18 to 24, 21.5% from 25 to 44, 36.2% from 45 to 64, and 14.1% who were 65 years of age or older. The median age was 45 years. For every 100 females there were 119.1 males. For every 100 females age 18 and over, there were 128.0 males.
The median income for a household in the CDP was $23,750, and the median income for a family was $23,000. Males had a median income of $33,750 versus $40,625 for females. The per capita income for the CDP was $16,183. There were 50.0% of families and 45.2% of the population living below the poverty line, including 60.0% of under eighteens and 25.0% of those over 64.