The crash happened at about 6 a.m. at Ninth and Brannan streets.
Police Officer Gordon Shyy said the tow truck was traveling north on Ninth Street and the pickup was headed west on Brannan when the two collided at the intersection, which is controlled by a traffic light.
The impact sent both vehicles crashing into separate buildings, Shyy said.
A woman who was a passenger in the pickup had to be extricated from the mangled car and was taken to a hospital, Shyy said. Her injuries are not considered life-threatening.
The driver of the pickup and the tow truck driver, who crawled out the passenger-side door of his vehicle, were treated at the scene, Shyy said.
Police are still investigating who was at fault for the crash.
The intersection was closed as the victims were treated and the crash was cleared.