American Mike Fossum, Japan's Satoshi Furukawa a nd Russia's Sergei Volkov touched down outside the remote settlement of Arkalyk in Kazakhstan just before sunrise after undocking from the ISS earlier in the day.
"It has landed," said a message flashed on the screen at Moscow mission control shown in a live relay. State television pictures showed the astronauts extracted from the capsule apparently in good health.
The Soyuz capsule landed on its side rather than its bottom after its descent to Earth with a parachute, mission control said, but such landing was not unusual. The landing was on time and on target at 0226 GMT.
The hitch-free landing of the Soyuz is a boost for the Russian space programme, which has been battling to restore confidence in its reliability after a spate of disasters in unmanned spaceflight. State television pictures showed ground workers moving quickly to carry the three men from the capsule to protect them from the initial shock of temperatures of minus 15 degrees Celsius after their half year stay on the ISS. Volkov was the first to emerge, followed by Fossum and Furukawa.
All were carried out by ground workers as the experience of prolonged weightlessness means that they cannot initially walk unassisted. They were then taken to a nearby medical tent put up next to the touchdown site to have their space suits removed and go through standard medical tests before being helicoptered to the northern Kazakh city of Kostanay.