The eligibility criteria for appearing GMAT is
The candidate must have completed 18 years of age
There is no upper age limit for the candidate
If the candidate is between 13 to 17 years old, they should have permission in writing from their parents or legal guardian
GMAC has not announced any official statement regarding qualification required to appear for GMAT
Candidates who wish to enroll for an MBA programme should possess a graduate degree in any discipline from a recognized university
ALL the best
If you see the above eligibility criteria then yeah you are eligible for GMAT.
I hope my answer helps. All the very best for your future endeavors!