DeShields, 17, is the son of 13-year major-league veteran Delino DeShields Sr. He is listed as both an infielder and outfielder. Financial aspects of the agreement weren't released.
"Delino fits perfectly into what we're trying to do at the development level," said Astros General Manager Ed Wade. "He is strong, athletic and dynamic. He's got great bloodlines and is focused on being a successful big leaguer."
DeShields was the eighth overall selection in the 2010 draft. He played both baseball and football at the Woodward Academy in College Park, Ga. He hit .415 with nine home runs, 40 runs batted in and 29 stolen bases as a senior.
He'll be assigned to the Astros' rookie league affiliate in Greenville, Tenn.