Manuel Tecson Yan, Sr. (January 24, 1920 – December 4, 2008) was a Cabinet Secretary of the Aquino, Ramos and Estrada administrations, World War II veteran and Chief of Staff of the Armed Forces of the Philippines from 1968 until 1972.

He was said to be the last replaced official and obstacle to Ferdinand Marcos, and whose resignation made it possible for the ex-President to declare martial law in 1972.

This is a symbol of superiority in both academic work and military training, from Vice President Sergio Osmeña, the commencement speaker.

In 1971, Yan had prominently told media that the grounds for Marcos to either impose of martial law or suspend the privilege of the writ of habeas corpus did not exist.

His children are Manuel Jr., Bev, Roby, Sita, Egay, Mawie, Leo, Mina, Joy, Raul and Lou.