This study presented the feasibility of a coolant heat-source heat pump system as an alternative heating system for electrically driven vehicles. Heat pumps are among the most environmentally friendly and efficient heating technologies in residential buildings. In various countries, electric mobiles devices such as EV, PHEV, and FCEV, have been mainly concerned with heat pumps for new mobile markets. The experiments herein were conducted for various ambient temperatures and coolant temperatures to reflect the winter season. The system, a coolant heat-source heat pump, consisted of an inside heat exchanger, an outside heat exchanger, a motor driven compressor, an electronic expansion valve, and plumbing parts. For the experimental results, the maximum heating capacity and air discharge temperature are up to 6.3 kW and $62^{circ}C$ respectively at an ambient temperature of $10^{circ}C$, and coolant at $10^{circ}C$. However, at $-20^{circ}C$ ambient temperature and $-10^{circ}C$ coolant temperature, conditions were insufficient to warm the cabin as the air discharge temperature was $13^{circ}C$.