Can a non-physician own a med spa in Rhode Island?

Short answer
Not directly — a professional corporation rendering medicine must have every officer, director, and shareholder licensed in that profession, though physicians, nurses, PAs and other listed professions may combine; other entity forms aren't addressed.

In a Rhode Island professional service corporation, every officer, director and shareholder must be a licensed practitioner — and must be employed by the corporation in that practice. a corporation organized under that chapter may render the professional services of NOT MORE THAN ONE of the enumerated professions, provided that every officer, director and shareholder is an individual authorized to practice that profession and is employed by the corporation in it; and no individual may be an officer, shareholder, director or employee of any other corporation practicing the same profession without the prior written approval of the applicable regulatory agency. The chapter then names the combinations it permits, the first of which groups physicians, dentists, registered nurses, podiatrists, optometrists, physician assistants, chiropractic physicians, physical therapists, psychologists, midwives and nurse-midwives. Investment is left open — the chapter does not prohibit such a corporation from investing its funds in real estate, mortgages, stocks, bonds or any investment not otherwise prohibited. And the eligibility rule has teeth: if a shareholder BECOMES ineligible they must transfer their shares to an eligible person or offer them to the corporation for redemption at fair-market value, and where transfer is blocked by the articles or bylaws the corporation SHALL redeem them and compensate the holder in full. Dividing fees, or agreeing to split or divide fees received for professional services with any person for bringing to or referring a patient, is unprofessional conduct.