According to deputies, the body was found in a canal near Miller Street in Anahuac.
A Silver Alert was issued for the 72-year-old woman earlier in the day.
Bettye Robinson was last seen Saturday at about 9:30 p.m. on North Main Street in Anahuac after leaving her son's residence on foot, officials said.
According to family, Robinson had early onset dementia and believed she was still in upstate New York.
Officials described Robinson as a Black female, 5 feet, 5 inches tall, with black hair and brown eyes.
The cause of death is unknown at this time.