There have been no claims of responsibility for the incident, although the news website Al Bawaba, based in Amman, Jordan, said the al-Nusra Front group -- aligned with al-Qaida -- typically takes responsibility for similar car bombings in the area.
Of those killed, five were civilians, the London-based Syrian Observatory for Human Rights said. No information on the other two victims was available. The Syrian state news agency added 25 people were injured in the explosion.
The incident occurred in a section of Homs generally loyal to President Bashar al-Assad.
Rebel forces withdrew from Homs in May, after a two-year offensive by the Syrian military which destroyed much of the city. While the withdrawal significantly reduced violence in the city, car bombs are still employed in pro-Assad neighborhoods.