First thing, you make sure you are recording the Deletion in your audit log. you can check here Configure audit settings for a site collection
Now following events available for audit log reports
The following events are available for audit log reports to help you determine who is taking what actions with the content of a site collection:
- Opened and downloaded documents, viewed items in lists, or viewed
item properties (This event is not available for SharePoint Online
- Edited items
- Checked out and checked in items
- Items that have been moved and copied to other location in the site
- Deleted and restored items
- Changes to content types and columns
- Search queries
- Changes to user accounts and permissions
- Changed audit settings and deleted audit log events
- Workflow events
- Custom events
View Log Reports: As you asked how can you view it.
To view an audit log report:
On the Settings menu, click Site settings.
NOTE The Site Collection Administration section will not be available if you do not have the necessary permissions, such as by being a member of the default Site Collections Administrators group.
- In the Site Collection Administration section, select Audit log
- On the View Auditing Reports page, select the report that you want,
such as Deletion.
- Type or Browse to the library where you want to save the report and
- On the Operation Completed Successfully page, click click here to
view this report.
Deletion reports looks like this
check this for more information.