The spacecraft, packed with nearly 2,700 kg of scientific gear, supplies and vehicle hardware, was lifted off at 5:42 a.m. local time (0942 GMT) from the Cape Canaveral Air Force Station in Florida.
About 10 minutes later, SpaceX's Twitter account confirmed Dragon was "in good orbit."
It is expected to reach the space station on July 2, spend approximately one month there, and then return to Earth.
The Dragon has flown before, supporting a mission in July 2016.
The robot, called "Crew Interactive Mobile Companion (CIMON)," will explore the use of AI as a way to mitigate crew stress and workload during long-term space flights.
CIMON, the first form of AI on an ISS mission, can see, hear and talk.
Also, a new investigation will examine whether cells cultured in microgravity can be a model system to test the effectiveness of new cancer treatment drugs.
Another study will explore how the microgravity environment of space affects microorganisms in the gastrointestinal tract.