An alumni of the National Defence Academy, Khadakwasla, Lieutenant General Harpal Singh was commissioned into the Corps of Engineers of the Indian Army in December 1982. He is a graduate of the Defence Services Staff College, Higher Defence Management Course and National Defence College. Lt Gen Singh has also held various prestigious staff appointments, which include instructor at the College of Defence Management, Secunderabad; as Additional Military Secretary, and also as Director General of Military Training at Army HQ.

During his 40 years of distinguished service, Lt Gen Singh has tenanted a number of critical command appointments at various levels, which include command of the Border Roads Task Force in the Jammu and Kashmir Valley; Chief Engineer (Navy), Mumbai, and Chief Engineer Eastern Command in Kolkata.

Furthermore, he is credited with the resurgence of the Border Roads Organisation (BRO) when he was at the helm of its affairs from March 2018 to November 2020 as Director General, Border Roads. Some of his major achievements include:

In his current capacity, he is heading the Corps of Engineers as the Engineer-in-Chief of the Armed Forces since December 1, 2020. Among many new initiatives during his present appointment, Lt Gen Singh has insisted on the use of the concepts of green buildings, green energy and latest technologies. He has also ensured the implementation of e-governance in the MES under Digital India Mission.