Hoesen was in a crowd in front of the net when he received a pass from midfielder Paul Marie, after midfielder Cristian Espinoza hurriedly took a corner kick and passed the ball to Marie. Hoesen one-timed a right-footed shot past Real Salt Lake goalkeeper Nick Rimando.
The late goal stretched San Jose's home unbeaten streak to eight games (7-0-1). Hoesen entered the contest in the 75th minute and provided the spark the Earthquakes needed.
Goalkeeper Daniel Vega made five saves for San Jose (8-7-4, 28 points). The Earthquakes are 5-1-2 in their past eight games.
Hoesen's goal spoiled Rimando's 500th career MLS contest. The 40-year-old was close to recording his third straight shutout before Hoesen beat him from close range.
Real Salt Lake (8-9-2, 26 points) fell to 2-7-2 on the road.
Salt Lake forward Sam Johnson (quadriceps) didn't make the trip to San Jose. Johnson has a team-high eight goals.
Salt Lake took 13 shots, and San Jose had 12. Salt Lake put four on target while San Jose had three.
Rimando made two saves.
RSL had a major chance in the 65th minute when Brooks Lennon made a nice run and delivered a swift pass to fellow midfielder Nick Besler on his left. Vega was out of position, but Besler sent the right-footed shot toward the far side of the net and missed it wide.
But overall, goal-scoring chances were slim in a match where tight marking was the priority from the outset.
Both teams took six shots in the first half. San Jose put two on target, and RSL had one.
Lennon had an opportunity in the 36th minute for RSL, but his right-footed blast from outside the box sailed wide right.
San Jose midfielder Judson stole the ball in the 43rd minute and immediately sent a right-footer from outside the box on goal. Rimando easily made the save.
Hoesen nets late winner for Quakes vs. RSL
Danny Hoesen finally found the net for San Jose breaking the deadlock and securing the 1-0 win over Real Salt Lake at home.