الجواب حامدا و مصلیا
If your parents are of Sahib e Nisab and they can bear up by themselves all the expenses in executing the obligation of Haj then in such a status Haj become Fardh (Obligatory) upon them. If they do not own the expenditure of Haj it does not become obligatory upon them just because you are rich and Sahib e Nisab. However if you make them perform Haj it will be a source of Sawab and reward for you and undoubtedly it will also be a great fortune for you.