The short answer
Yes. Rebuilt or re-downloaded automatically when needed.
What is it?
Temporary data of Microsoft Excel inside its sandbox container, such as web content, add-in data and downloaded resources.
What happens if you delete it?
Excel rebuilds it as needed, and some resources download again. Workbooks, AutoRecover files and settings are stored elsewhere.
How to remove it properly
Quit Excel, then move ~/Library/Containers/com.microsoft.Excel/Data/Library/Caches to the Trash.
Quit the app that uses it, then move it to the Trash. Empty the Trash when you’re sure.
How MoreRoom helps
MoreRoom recognises this item, shows its real size and when it was last used, and labels it “Safe to remove”. In the free version you can move it to the Trash in one click, with Undo; Pro collects every safe item at once.
Frequently asked questions
Is it safe to delete the Microsoft Excel cache on Mac?
Yes. Rebuilt or re-downloaded automatically when needed. Excel rebuilds it as needed, and some resources download again. Workbooks, AutoRecover files and settings are stored elsewhere.
Will Microsoft Excel cache come back after I delete it?
Yes. Excel rebuilds it as needed, and some resources download again. Workbooks, AutoRecover files and settings are stored elsewhere.
How do I remove Microsoft Excel cache properly?
Quit Excel, then move ~/Library/Containers/com.microsoft.Excel/Data/Library/Caches to the Trash.