My employee claims "0" on his W4. Both he and I are paying the maximum tax (w2 employee). If the employee files taxes and gets a tax refund, will I also get a tax refund?

Welcome to the Community, Jeff. 

As much as I'd like to answer your question, we're unable to provide information about getting a tax refund. We can only guide you on how to enter it in QuickBooks. That said, I highly suggest reaching out to the IRS to verify the details you need.

Moreover, I'm sharing this article for your additional information about payroll tax: Resolve a payroll tax overpayment. You'll want to expand the QuickBooks Online section to see the detailed steps for recording overpayments.

Feel free to leave a reply if you've got additional questions or need assistance recording tax refunds in Quickbooks. I'll be here to help you out. Take care and have a good one!