Pedestrian and Bicyclist Safety Improvement Act of 2020 This bill directs the Department of Transportation (DOT), every two years, to conduct nationwide on-the-ground road safety assessments focused on pedestrian and bicycle safety in each state. The purpose of the assessments is to identify and examine specific locations with documented or perceived problems with pedestrian and bicycle safety and access, examine barriers to providing safe pedestrian and bicycle access to transportation infrastructure, and develop and issue recommendations designed to effectively address specific safety and access issues and enhance pedestrian and bicycle safety in high-risk areas. DOT must maintain a national pedestrian and bicycle safety database that includes (1) a list of high-risk intersections, roads, and highways with a documented history of pedestrian or bicycle accidents or fatalities and details regarding those incidents; and (2) information on corrective measures that have been implemented at the state, local, or federal level to enhance pedestrian and bicyclist safety at those high-risk areas, including details on the nature and date of corrective action.