The H-IIB was a liquid-fueled rocket, with solid-fuel strap-on boosters and was launched from the Tanegashima Space Center in southern Japan.

Its performance to low Earth orbit (LEO) was sufficient for the 16,500 kg (36,400 lb) H-II Transfer Vehicle (HTV).

The system was designed to adopt methods and components that have already been verified by flights on the H-IIA, so that manufacturing the new launch vehicle would be more cost-effective, with less risk, in a shorter period of time.

JAXA was in charge of preliminary design, readiness of the ground facility, and the development of new technologies for the H-IIB, in which the private sector has limited competencies, while the Mitsubishi Heavy Industries was responsible for manufacturing.

The first test, which consisted of firing the first stage for ten seconds, was originally scheduled to occur at 02:30 UTC on 27 March 2009, however it was cancelled after the launch pad's coolant system failed to activate.

[7] The test was rescheduled for 1 April 2009, but then postponed again due to a leak in a pipe associated with the launch facility's fire suppression system.