Move Dashboards Between Folders in the Lightning Experience Dashboard Builder

If your org is using Enhanced Analytics Folder Sharing for Reports and Dashboards, folders govern who has access to the reports and dashboards saved inside. (If your org was created after the Summer ’13 Salesforce release, you already have Enhanced Analytics Folder Sharing.) To move a dashboard from one folder to another, open the Properties menu in the Lightning Experience Dashboard Builder. This feature is new in Lightning Experience.
Moving a dashboard into another folder