Russian space officials say the docking took place on schedule two days after the Soyuz blasted off from the Baikonur Cosmodrome in Kazakhstan.
American astronaut John Phillips, Russian Sergei Krikalyov and Italian Roberto Vittori later opened the hatch and made their way into the orbiting space complex.
There they joined Russian cosmonaut Salizhan Sharipov and American astronaut Leroy Chiao, who've been on the space station for the past six months.
All five men soon appeared in a live television hook-up with mission control back on earth.
Mr. Sharipov welcomed the new men on board and said that all was ready for the transfer of crews on the station.
Mr. Phillips and Mr. Krikalyov are to spend the next six months on board.
One of their main tasks will be to welcome the return of an American space shuttle to the station for the first time in two years.
The shuttle Discovery is due to dock with the space station next month after a two-year break due to the disintegration of the shuttle Columbia, which killed all seven astronauts on board.
The new crewmen on the station will conduct a photographic survey of Discovery as it moves in for docking.
This will help determine if extensive work on the shuttle's exterior insulation system has been successful.
It was a failure of that system that caused Columbia to break apart in the intense heat generated when it reentered earth's atmosphere.
Italian Roberto Vittori is with the European space agency. He is due to conduct a series of experiments over the next eight days before returning to earth in the Soyuz capsule with Mr. Sharipov and Mr. Chiao.
The Soyuz craft have served as the only link with the station since all shuttles were grounded after the Columbia accident.