NASA astronaut Michael Foale and Russia's Alexander Kaleri blasted off in a Soyuz TMA-3 from Russia's Baikonur cosmodrome in Kazakhstan on Saturday at the start of their 200-day mission.
Spaniard Pedro Duque has accompanied them and will do a week of experiments before returning to Earth with the outgoing team, which was waiting on the station for the new crew to arrive.
"Everything went well, as expected. There was no need for interference by the crew," a mission control official said by telephone shortly after the docking. "The docking was at 1116 hrs (0716 GMT)."
After checking for leaks, the new crew is expected to crawl through a hatch into the station and meet their fellow astronauts at about 1000 GMT.
American Edward Lu and Russian Yuri Malenchenko have not seen anyone but each other for six months, although Malenchenko managed to overcome the initial objections of Russian space officials and marry his fiancee via a satellite video link.
"Everything went well, as expected. There was no need for interference by the crew"
Unnamed Russian mission control official
The ISS project's survival depends on Russia, which has launched all manned and cargo flights to the station since February when the US Columbia shuttle disintegrated on re-entry, killing seven crew on board.
Funding concerns plague the ISS, with Russia saying it needs more money to continue servicing it.
Uncertain finances could prompt a delay in the launch to the station of the next Progress cargo ship, from November to January.
The success of China's first manned flight last week has sparked speculation that it could join the ISS venture.