The beneficiaries of Zakah (obligatory charity) are explained in Allah's (Exalted be He) Saying:
As-Sadaqât (here it means Zakât) are only for the Fuqarâ’ (poor), and the Masâkin (needy) and those employed to collect (the funds), and to attract the hearts of those who have been inclined (towards Islâm), and to free the captives, and for those in debt, and for Allâh’s Cause, and for the wayfarer (a traveller who is cut off from everything); a duty imposed by Allâh. And Allâh is All-Knower, All-Wise.
It is understood from your description of the state of your relative that he is not poor and that his salary will be sufficient for him if he spends wisely without extravagance or lavishness. However, there is nothing wrong with you giving him some money, gift or loan with the intention of helping him and you will be rewarded, In sha’a-Allah (if Allah wills). (Part No. 8; Page No. 365) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.