European Space Agency astronaut Samantha Cristoforetti grappled the capsule with the space station's robotic arm at 6:55 am local time as the space station flew over the northern Pacific to the east of Japan, NASA said.
"Houston, capture is complete," said NASA astronaut Terry Virts, after high-fiving Cristoforetti in the space station's cupola.
"Samantha did a perfect job grappling Dragon."
The cargo ship will move closer to the space station and complete its latch-on later today.
SpaceX launched the cargo ship on Tuesday from Cape Canaveral, Florida, on its sixth official mission under a USD 1.6 billion contract with NASA for a dozen trips to supply the orbiting space station.
The Dragon made history in 2012, when it became the first commercial cargo ship to reach the space station.
Previously, only government-built spaceships from Europe, Japan and Russia were able to make that journey.
The US-made space shuttles were also big enough to carry cargo along with astronauts, before the program was retired in 2011.
Boeing is also working on a spaceship to ferry astronauts to space, called the CST-100, which is scheduled for its first manned flight in 2017.
Until then, the world's astronauts must rely on Russia's Soyuz capsules for transport to the research outpost.
