There doesn't seem to be a way of preventing users from creating wiki pages altogether out of the box in my opinion.
However, There are two ways you can achieve your requirement.
Option 1 - Using some JavaScript and CSS tricks in a Delegate Control, you can restrict the users from creating wiki pages in your site. This can be done by adding a delegate control to your site that would sit in your document libraries and check for its SPLISTTEMPLATETYPE
. If it's value is WebPageLibrary (Wiki Page Library - 119), then New Document link on the view and the New Document and Upload Document commands on the ribbon can be disabled or hidden using JavaScript and CSS.
Pros
- Will work even on the newly created wiki page libraries
Cons
- Would require writing code.
Option 2 - By Breaking Permission Inheritance
Go to your Wiki Page Library Settings -> Permissions for this Library
Under Permissions tab on the ribbon, Click on Stop Inheriting Permissions
Click Ok on the dialog box.
Select all the users and groups you want to restrict from creating pages, and click on Edit user permissions in the ribbon.
Assign the users and groups selected Read permissions.
Pros
- Completely Out of box and no-code solution, easy to implement
Cons
- Only issue with this approach is that you will need to break the permission inheritance of each wiki page library and whenever a new library is created.