If the following circumstances are met,
1. parents reside in US residents,
2.parents are Legal residents,
3.you provide more than 50% support to them (you must be able to provide
4.the parents are not claimed by other relatives or themselves on their personal tax,
5.there is relationship, in this case they are your parents!
In these circumstances, then IRS will permit you to claim them as dependents on your personal tax return.