Major General Senanayake was appointed the Army Chief of Staff on 22 March 2017, and was then promoted to the rank of Lieutenant General and Army Commander by order of President Maithripala Sirisena on 4 July 2017. During his tenure the army was mobilised and deployed on several occasions, in aid of civilian authorities when a state of emergency was declared as a result of the 2018 anti-Muslim riots and the 2019 Easter bombings bring the security situation under control. On 21 August 2019, he retired from the army, having been promoted to the rank of General. He was succeeded as Army Commander by Major General Shavendra Silva, the Chief of Staff of the army.