UITableview cells height is not working in a empty table?

You should be able to force a row height at all times by setting rowHeight, even if the row count is 0.

self.tableView.rowHeight = 75.0;

You can also set it in IB.

heightForRowAtIndexPath seems to only be called if a cell is being set up in cellForRowAtIndexPath, whereas this is a property of the tableview and is always present.