1. When you logon to the SAP Fiori Launchpad, you will see standard background image for SAP Fiori Launchpad login page.
2. Go to transaction code SE80. Choose MIME Repository.
3. Navigate to SAP → PUBLIC → BC → UI2 → logon → img. Expand “img” folder you will find different background jpg images.
4. Choose login_background.jpg , right-click and choose Upload/Download → Upload and Replace
5. In the File explorer choose the new image. The name of your new image should be the same “login_background.jpg”. Save the changes in the transport request.
6. Now logon again into SAP Fiori Launchpad by accessing the launchpad url, you should see your new image as background.
You can observe background image for SAP Fiori Launchpad Logon is being changed now.