I am sure most Project Server users are well versed with the procedures for renaming a project in Project Server. However, this question (or related) comes up pretty regularly in the Project Server Forums, so hopefully this article will serve as a reference for this topic.

When you are using Microsoft Project as a stand-alone product, without it being connected to Project Server, then renaming it is the same as renaming any other file, document. However, when you are connected to the server, things are slightly different. These steps are covered in details below.

Note: My screenshots show Project Server 2013, but the procedure is also valid for Project Server 2010.

Renaming the project from PWA

Renaming the project from Microsoft Project

You could also rename the project from Microsoft Project, as below.

Start by opening Microsoft Project, connected to the PWA instance that you are working with.

Click File >> Open to bring the Open project dialog box.

Click on Show me the list of all projects to bring up the list of all projects on the server.

Right click on the name of the project that you want to rename, and select Rename.
Type the new name and hit Enter. You will be presented with a pop-up box similar to the one below.
Click OK. You should see the new Project name displayed. (You might have to close the dialog box and reopen to see the change).

Note: When you rename a project with this method, you will need to publish the project before you can see the name update in PWA.

Renaming the Project Site

If you are using the Project Sites functionality (a SharePoint site that gets created when you create/publish a project), then it is best practice to rename the project site as well, when you rename a project. Otherwise, the Project Site will continue displaying the old name and URL< which might confuse the users.

Renaming a project site has two steps, as detailed below.

Step 1: Rename the Site

Start by navigating to the Project Site, by clicking on the Project Site link.

Click on the gear icon on the top right corner, and the click on Site Settings in the drop down menu.

Under the look and feel section, click on Title, description and logo.
Under the Title and Description, change the name to match the project name. Do the same for the Website Address, in case you want the URL also to match the project name.

Step 2: Edit Site Address

If you changed the URL of the Project Site in Step 1 of this section, then you will no longer be able to access the Project Site by clicking Project Site in project center. To fix this, follow the steps below.

Navigate to Server Settings >> Connected SharePoint Sites

Select the site that you just changed the address of, and click on Edit Site Address from the menu bar.

On the Edit Site Address dialog box, enter the new site URL, test it to make sure it works and click OK.

That’s it. This is the full procedure for renaming a project, along with the connected SharePoint Sites.

Couple of caveats

If there are timesheets reported on the project while it had the old name, the timesheets will continue showing the old name, until recalled, deleted and recreated.
If there are previous timesheets submitted/approved while the project had the old name, the Timesheet tables in Reporting database will retain the actual values against the old name. So some of your timesheet reports might show both old and new names.
If any of your users have pinned the previous site address, you will need to let them know about the new site site URL.