Police said the driver had been cooperative, and it appeared slick roads and dark driving conditions made it difficult to see or stop.
The man who was hit died at the scene.
He had been walking in the road wearing dark clothing, and the driver didn't see him until it was too late, Lt. Lance VanDongen said.
"The roads were wet, it was dark, it wasn't easy to see, " VanDongen said. "There's no crosswalk in that area."
Less than five hours later, an SUV spun off the road near 800 South and Interstate 215, according to the Utah Highway Patrol.
The woman behind the wheel of the 2005 Mazda Tribute was driving northbound around 3:55 a.m. when slippery roads apparently caused her to lose control of her vehicle, the UHP said.
She crashed into a retaining wall and was then hit by another car.
The second car, a Mitsubishi Galant, spun out in the exact same spot she had, but that driver was not harmed.
The woman, who was not initially identified, was taken to a local hospital, where she later died.
About a half an hour later, another crash claimed the life of a male driver when his SUV collided with a detached trailer in the industrial area of 400 West and 700 South, police said.
The man, who was not named, was the only person in the car when he crashed about 4:35 a.m. He was pronounced dead on scene.
Salt Lake Police investigators, who were still gathering information about the crash around 7 a.m. Monday, said it was unclear if weather was a factor in this crash, but they believed the man had been speeding when he hit the parked trailer.
The speed limit in that area is 25 mph.