The National Security Bureau (NSB) (Arabic: جهاز الأمن القومي (اليمن)) is a state security intelligence-gathering agency of Yemen, responsible for the protection of the country from acts of foreign interference.

The NSB reports directly to the office of the President of Yemen.

NSB was established in 2002 by President Ali Abdullah Saleh.

It was led by Ali Mohammed al-Ansi since its establishment until 2012.

Following an assassination attempt that targeted the defence minister in Sana'a with a car bomb, President Abdurabbuh Mansur Hadi sacked both and appointed Ali al-Ahmadi as chief of the NSB on 1 September 2012.