Can I claim my 31 year old daughter on my income tax. She lives with me and I pay everything for her. She has no job.

If you provide more than HALF of her total support and her own earned income is LESS than her $3,900 personal exemption, then, yes, you can claim her on your income tax return as a dependent.

I agree with ATE. You can claim her as a dependent relative, but not as a dependent child