Gibson, a longtime employee in the Baltimore mayor's office, succeeds Nathaniel Oaks, who moved to the state Senate this month. Oaks filled a Senate seat vacated by Lisa Gladden, who resigned for health reasons.
Gibson was selected for the position this month by the Democratic State Central Committee for the 41st District.
"I am confident that Angela Gibson is prepared to serve her constituency in Baltimore City," Hogan, a Republican, said in a statement announcing the appointment. "I offer her my sincere congratulations and look forward to working with her to continue changing Maryland for the better.
Gibson's appointment ends an extended shuffling of seats in the General Assembly, primarily in Baltimore's delegation. In addition to Gladden's resignation, Baltimore Mayor Catherine Pugh resigned her seat in the Senate after winning the city election and other lawmakers left the legislature to work for Pugh.
The General Assembly is at the midpoint of its annual 90-day legislative session.