I’ve heard a number of requests for the ability to reorder Power View sheet tabs in Excel 2013. While this is currently a bug that will be fixed in the future, there is a work-around to do this now.
Assuming you have a workbook that contains a number of Power View sheets and you want to move the last one you created (“Power View4” in the screenshot here) to be the leftmost tab in the workbook.
First, click on the plus sign to create a new Excel sheet.
Move that sheet to be next to the Power View sheet you want to move. With the new Excel sheet selected, hold down the control key and click on the Power View sheet you want to move so that both tabs are selected.
Now, click and drag the Excel sheet to the desired location. The Power View sheet will come along for the ride.
When the Power View sheet is in the desired location you can select and delete the new Excel sheet that you created.