Jones studies medicine at King's College, London and qualified with MRCS, LRCP from Westminster Hospital Medical School in 1939. He stayed on at the hospital to complete his junior house posts. Between 1942 and 1946, he joined the Royal Army Medical Corps as a regimental medical officer to a field artillery regiment in North Africa and Italy. He witnessed the Salerno landing and the attack on Monte Cassino. Declining an elevation in rank, he opted to endure the rest of the war along with his regiment. Returning to England in 1946, Jones continued his surgical training and passed the FRCS in 1948. Afterwards, he joined the surgical team under Sir Clement Price Thomas at the Brompton Hospital and Westminster Hospitals.