Mostafa Mohammad Najjar said Iranian military specialists "are creating types of weapons that have no equal in the world."
He added that Iran would continue to build up its defense capability to ensure regional stability and security.
"Our greater defense power is no threat to other countries," he said. "Iran only needs a system to deter and repulse possible external aggression against it."
Iran said on Monday it had successfully test-fired a heat-seeking air-to-air missile. The Defense Ministry said the new missile, which has a range of 100 kilometers (62 miles), will go into production after the tests are completed in March.
Tehran announced last November it had successfully test-fired a new surface-to-surface solid-fuel missile, called Sajjil, with a range of about 2,000 km (1,200 miles).
It earlier test-launched an upgraded Shahab-3 ballistic missile as part of the Great Prophet III military exercise in the Persian Gulf and the Strait of Hormuz, drawing a new wave of international criticism.