Yes. If you are the noncustodial parent, the IRS requires you to attach Form 8332 (or equivalent) to your tax return for each year you are claiming the exemption. If you are filing your return electronically, you'll attach the 8332 to Form 8453, which is mailed to the IRS.
For more information, please see the instructions on IRS Form 8332,
Release/Revocation of Release of Claim to Exemption for Child by Custodial
Parent.
