Flight controllers at NASA's Mission Control in Houston stepped in to drive the capsule to its berthing port on the station's Harmony connecting node. Docking occurred at 8:44 a.m. EST.
The spacecraft arrived a day late due to mechanical problems after Friday's launch from Cape Canaveral, Fla.
Three of its four steering thruster pods failed to activate properly after it reached orbit, threatening to scuttle the cargo delivery mission. However, SpaceX engineers were successful in fixing the trouble and continuing the mission. A planned arrival at the station on Saturday was pushed back a day.
SpaceX, otherwise known as Space Exploration Technologies Corp. is the first private company to fly to the station, a $100 billion project of 15 nations.
Among the items being delivered: 640 seeds of a flowering weed used for research, mouse stem cells, food and clothes for the six men on board the space station, trash bags, computer equipment, air purifiers, spacewalking tools and batteries. The company also tucked away apples and other fresh treats from an employee's family orchard.
Once the capsule is unloaded, about 3,000 pounds of experiment samples, broken equipment and other gear will be brought back aboard the spacecraft, which is scheduled to splash down in the Pacific Ocean off the coast of Baja California on March 25.
Dragon is the only station freighter that makes return trips, a critical service that was lost after the U.S. shuttle program ended in 2011. While cargo ships flown by Russia, Europe and Japan can deliver supplies, they burn up on re-entry into the atmosphere after leaving the station.
This cargo delivery mission was the second of 12 planned under a $1.6 billion NASA-SpaceX contract.
SpaceX and other companies are working toward launching astronauts by 2015 on modified versions of the cargo spacecrafts.