The launch of the Kavoshgar-3, which means Explorer-3 in Farsi, was announced by Defense Minister Gen. Ahmad Vahidi as part of Iran's ambitious space program. It comes a year after Iran sent its first domestically made telecommunications satellite into orbit.
The program has worried Western powers who fear the same technology used to launch satellites and research capsules could also deliver warheads.
Iranian state television broadcast images Wednesday of officials putting a mouse, two turtles and about a dozen creatures that looked like worms inside a capsule in the rocket before it blast off.
Vahidi gave no details on the research and the report did not disclose when or where the launch took place.
The rocket is the third in a series bearing the same name. Iran reported launching Kavoshgar-1, or Explorer-1, in Feb. 2008. The first section of the rocket detached after 90 seconds and returned to earth with the help of a parachute. A second segment entered space for about five minutes, while the final section was sent toward orbit to collect data.
Later in 2008, a rocket entitled Kavoshgar-2, or Explorer-2, made it to the lower reaches of space and returned to earth 40 minutes later on a parachute. No details about that launch were reported.
Ahmadinejad praised the latest launch and said greater events would come in the future.
"The scientific arena is where we could defeat the (West's) domination," Ahmadinejad said in remarks broadcast live on state TV. He said the launch is a "very big event. This is the first presence of animals in space launched by Iran. It's the start of bigger achievements" to come.
Also Wednesday, Ahmadinejad unveiled a new domestically built light booster rocket, named Simorgh, as well as three Iranian-built satellites -- Mesbah-2, Tolo and Navid-e-Elm-o-Sanat -- all part of Iran's observing the National Day of Space Technology.
Officials said the Simorgh rocket can carry a satellite weighing 220 pounds (100 kilograms) up to 310 miles (500 kilometers) above the Earth.
As it seeks to expand its influence in the Middle East, Iran touts such technological successes as signs it can advance despite the threat of U.S. and U.N. sanctions over its controversial nuclear program.
The West is concerned Iran is trying to build an atomic weapon but Tehran denies the charge and says it's nuclear program is only for peaceful purposes, such as electricity production.
Ahmadinejad said Iran built the Mesbah-2 with domestic technology after foreign partners refused to cooperate. He didn't name any country, but Iran said last year that it plans to launch a communications satellite by late 2011 with no outside help, after Italy and Russia declined to put it into orbit.
Its predecessor, the Mesbah-1 satellite, was first displayed in 2005. Iran planned to launch it the same year with Russian help but Moscow repeatedly delayed providing a satellite-carrier.
"Mesbah-1 had a sad fate ... they didn't have the courage to launch our satellite," Ahmadinejad said. He added that the Mesbah-2 would be launched using an Iranian-made rocket.
Iran's lofty space plans also include putting a man in orbit within 10 years.
In 2005, Iran launched its first commercial satellite on a Russian rocket in a joint project with Moscow, which is a partner in transferring space technology to Iran. That same year, the government said it had allocated $500 million for space projects for the next five years.
The ceremony Wednesday was part of 10-day celebrations leading up to 31st anniversary of the Islamic Revolution, which falls on Feb 11.