The news agency Fars, owned by the office of Irans Supreme Leader Ayatollah Ali Khamenei, reported that it was unclear whether Ahmadinejad had accepted Tahmasbis resignation.
The report did not state the reason for the resignation.
Tahmasbi, 46, is a former senior officer in Jihad Sazandegi and a former head of Jihad Sazandegi Research Centre.
He was once a Revolutionary Guards officer in Khatam-ol-Anbia Garrison of the Islamic Revolutionary Guards Corps (IRGC). Tahmasbi is an expert in ballistic missile development.