The successful mission marks a significant victory in the race toward commercial space travel and is expected to eventually lead to astronauts and supplies being delivered by private companies to the International Space Station.
The Falcon 9 rocket and Dragon spaceship are the property of SpaceX, a company funded in part by multimillionaire Elon Musk, who made a fortune from the online payment system PayPal.
The unmanned ship lifted off at 10:43 a.m., after its 9 a.m. launch was delayed. It circled the Earth twice before landing in the Pacific, about 500 miles off the Mexican coast, at about 2 p.m. EST.
It was the first re-entry from orbit by a spacecraft owned by a private company.
Last spring, the Obama administration scuttled the new rocket and spaceship NASA was building to replace the space shuttle, which retires next year. Instead, the administration wants to rely on space vehicles provided by private companies.