Permission Set Assigned Users Page

From the Assigned Users page, you can view all users who are assigned to a permission set, assign additional users, and remove user assignments.
Available in: Salesforce Classic and Lightning Experience
Available in: Contact Manager, Professional, Group, Enterprise, Performance, Unlimited, Developer, and Database.com Editions

User Permissions Needed
To view users that are assigned to a permission set: “View Setup and Configuration”

To view all users that are assigned to a permission set, from any permission set page, click Manage Assignments. From the Assigned Users page, you can: