My ex is claiming my daughter in his taxes but he don't taker to much of her and I want to claim her in my taxes how what can I do

Who has primary residential custody? The IRS requirement is that the parent who has the child at least 51% in his or her residence is the one who can claim the deduction. If the daughter lives with your ex, then he would have the exemption. Otherwise, you should have it unless there was some type of agreement between the two of you in your property settlement agreement.