Del Rey first appeared as a census designated place in the 1980 U.S. census.
!Pop 2010
!style="background-color: #ffffb3;" |Pop 2020
!% 2000
!% 2010
!style="background-color: #ffffb3;" |% 2020
|-
|White alone (NH)
|54
|59
|style='background: #ffffe6;' |73
|5.68%
|3.60%
|style='background: #ffffe6;' |5.38%
|-
|Black or African American alone (NH)
|0
|0
|style='background: #ffffe6;' |12
|0.00%
|0.00%
|style='background: #ffffe6;' |0.88%
|-
|Native American or Alaska Native alone (NH)
|0
|4
|style='background: #ffffe6;' |2
|0.00%
|0.24%
|style='background: #ffffe6;' |0.15%
|-
|Asian alone (NH)
|7
|34
|style='background: #ffffe6;' |45
|0.74%
|2.07%
|style='background: #ffffe6;' |3.31%
|-
|Native Hawaiian or Pacific Islander alone (NH)
|0
|0
|style='background: #ffffe6;' |0
|0.00%
|0.00%
|style='background: #ffffe6;' |0.00%
|-
|Other race alone (NH)
|0
|0
|style='background: #ffffe6;' |2
|0.00%
|0.00%
|style='background: #ffffe6;' |0.15%
|-
|Mixed race or Multiracial (NH)
|1
|8
|style='background: #ffffe6;' |17
|0.11%
|0.49%
|style='background: #ffffe6;' |1.25%
|-
|Hispanic or Latino (any race)
|888
|1,534
|style='background: #ffffe6;' |1,207
|93.47%
|93.59%
|style='background: #ffffe6;' |88.88%
|-
|Total
|950
|1,639
|style='background: #ffffe6;' |1,358
|100.00%
|100.00%
|style='background: #ffffe6;' |100.00%
|}
2020 census
As of the 2020 census, Del Rey had a population of 1,358 and a population density of .
The age distribution was 356 people (26.2%) under the age of 18, 161 people (11.9%) aged 18 to 24, 386 people (28.4%) aged 25 to 44, 292 people (21.5%) aged 45 to 64, and 163 people (12.0%) who were 65years of age or older. The median age was 31.7years. For every 100 females, there were 105.4 males, and for every 100 females age 18 and over, there were 102.4 males age 18 and over.
Income and poverty
In 2023, the US Census Bureau estimated that the median household income was $57,292, and the per capita income was $18,548. About 28.2% of families and 24.8% of the population were below the poverty line.
Education
It is in the Sanger Unified School District.<!--UNI 35250-->