The Portland Bureau of Transportation (or PBOT) is the largest bureau at City of Portland tasked with maintaining the city of Portland's transportation infrastructure. Bureau staff plan, build, manage, and maintain a transportation system with the goal of providing people and businesses access and mobility. The Bureau received significant media coverage in 2017 for employee hazing within its maintenance operations, as well as a bribery scheme between its parking manager and Cale America that span from 2002 to 2011 for which the manager Ellis McCoy was sentenced to two years in federal prison.

Previously, the mayor assigned a city commissioner to be in charge of each Portland bureau, who would then appoint a director. However, a charter reform voted into place in 2022 and enacted in 2025 stipulates that bureaus would be moved out of the portfolios of city commissioners. The last city council member to oversee this bureau was commissioner Mingus Mapps in 2024, who hired current bureau director Millicent Williams in July 2023. The bureau is now under the umbrella service area Public Works, headed by Deputy City Administrator for Public Works Priya Dhanapal.

In June 2013, Mayor Charlie Hales appointed Steve Novick commissioner in charge. Novick appointed Leah Treat director in July 2013 following a nationwide search. She replaced Interim Director Toby Widmer, who had been appointed following the resignation of former Director Tom Miller. Interim director Chris Warner replaced Leah Treat in July 2018 after Treat's resignation.

According to the 2014-2015 budget, the Bureau is led by the Office of the Director, which directly oversees communication and six division managers as follows:

The City Auditor ombudsman's office which takes in complaints from the general public concerning city bureaus reported in its 2018 annual report that they routinely receive the most complaints about PBOT. They concluded that "several of our complaint investigations found structural unfairness within transportation programs, requiring reform." Sidewalk and vehicle towing concerns represented the greatest number of complaints made with the ombudsman's office about PBOT in 2001. In 2023, PBOT was also the top complaint filed with the ombudsman's office, accounting for 28% of all complaints filed with ombudsman's office.

In May 2017, Willamette Week first reported PBOT's maintenance leader had subjected subordinates to various forms of hazing, such as shooting BBs and popcorn kernels at them. The report obtained by the paper which was based on interviews with nine employees characterized the workplace culture at PBOT maintenance shop as a place of "violence, hazing and bigotry inside a shop that prizes loyalty and punishes "snitching." The investigation was focused around a longtime city employee Jerry Munson who was the crew leader for the "liner crew" maintenance branch. After learning of hazing, city officials transferred the "ring leader" and terminated one of the whistleblowers. An internal investigation of the agency later yielded a pattern of "workplace harassment, intimidation, discrimination, dishonesty, retaliation on the basis of sexual orientation and physical violence". One victim, Adam Rawlins, said that between Augusts 2016 and December 2016, he had been subject to numerous pranks by other employees while he was working at PBOT. His lawsuit, which sought $250,000, indicated that pranks included "being locked in a dark shed while being bound with duct tape and zip ties." The city settled with Rawlins for $80,000 citing "risk the city may be found liable."

The parking enforcement division under PBOT enforces city's parking regulations per title 16 chapter 16.10 of city code. A consultant report obtained by The Oregonian reported Parking Enforcement Division's method is "unprofessional and leaves room for “favoritism” and “illegal conduct"

A 2002 study in Seattle reported Portland had a total of 30 parking enforcement officers which amounted to one for every 237 parking spaces. The average of six cities in the study had one officer for every 93 spaces.