In Ghana, private higher education institutions' (PHEIs) share of gross tertiary enrolment is on the decline in the midst of growing demand for tertiary education. Whether this is, an indication of PHEIs in Ghana becoming endangered species in the higher education space has received limited research attention. Through documentary reviews and interviews of purposively selected 22 key informants, including Presidents, Vice Presidents, Registrars, Finance Officers of PHEIs and Ghana Tertiary Education Commission (GTEC) Academic Auditors, this study investigates the viability and sustainability of PHEIs in Ghana. Resource Dependency Theory guided the study. The emerging issues, which relate to dynamics of students' enrolments, funding, affiliation policy, staffing and innovativeness provide indicative realities of short-term viability and long-term sustainability of PHEIs in Ghana that make them appear endangered species. The study concludes that PHEIs in Ghana are vulnerable with respect to their short-term operational viability and long-term sustainability which make them appear endangered species with a plausible implication of heightening the pressure on the public purse to expand and or establish more public HEIs in order to meet the ever-increasing demand for higher education.