Starting his career as a math teacher at Phú Xuân Private School, Providence Thuận Hóa School (Huế), and “no one ever thought that a gentleman teacher like him would become an outstanding strategy general".

Photo: Teacher Cao Văn Khánh (the second person as seen from the right), the photo was taken with professors at Phú Xuân School, Huế, 1940

"I just want to be a good citizen. When the country needs help, then I go to the front. When everything is back to normal, I'll be a teacher again. That's what makes me satisfied.” When the Resistance war against the French broke out, he held positions such as: Head of Area V, Deputy Chief of Battalion 308, Director of Military Training Department under the General Staff, Director of the Department of Planning-cum- Director of the Department of Schools... In the resistance war against the US, he repeatedly served as Commander of the Central and Central Highlands battlefields and eventually became the Deputy General Staff (1974).

Photo: Deputy Chief of the General Staff Cao Văn Khánh (first person from the left) and leader of the Standing Group, directed strategic operations established by General Võ Nguyên Giáp on April 12, 1975

Colonel Cao Van Khanh, deputy commander of the Battalion 308 had just left Area V for the North (first person from the left), in 1949

Deputy Commander-cum-Chief of Staff Cao Văn Khánh, the photo was taken after the battle in Dak To, Central Highlands, October 1967

During his nearly 30 years of military career, he was always present on the battlefield to command the fiercest battles to winning strategic victories such as: Thao River (1949), Border (1950), Điện Biên Phủ(1954), Khe Sanh (1968), Trail 9 (1971), Central Highlands(1972-1974)…

Comrade Cao Van Khanh on the Trị - Thiên battlefield, 1968 - 1971

Colonel Cao Văn Khánh at the headquarters of Trail 9 front, April 18, 1970

Colonel Cao Văn Khánh and Chief of the General Staff Văn Tiến Dũng on the battlefield in Quảng Trị, 1972

Colonel Cao Văn Khánh, Commander of the B5 Front, received General Võ Nguyên Giáp at the Headquarters in Quảng trị in January 1973

“It has become a habit that every time I have difficulty in leadership at a macro level, I often consult with many officials, especially those with experience in advisory work and commanders who participated in the war. Democracy in the military always brings good suggestions, good ideas… Comrade Cao Văn Khánh was Deputy Chief of the General Staff of this group." ("The Headquarters in the Victorious Spring - General Võ Nguyên Giáp)

Photo: Deputy Chief of the General Staff Cao Văn Khánh (the second person from the left) and comrades in Headquarters prepared for a plan to attack Đà Nẵng, March 1975

General Cao Văn Khánh had a romantic wedding held in the middle of a fierce battlefield in Điện Biên:
“It was a special wedding held right in the bunker of General De Castries in the middle of a battle in Mường Thanh. While the fire was still burning, the wedding of a female medic and the Deputy Commander of the Brigade 308 took place. The cellar was decorated brilliantly, the decorations were colorful parachute-trophies. Tables and chairs were covered with flower parachutes, in the front hung a a red parachute with the words "Enjoy the new happiness but don't forget the mission 22/5/1954". The reception party was as luxurious as a European wedding with Champagne, Napoleon from Paris, cigarettes. They were high-class French trophies that had been dropped by parachute and flown into our battlefield. From the bunker of General De Castries, we came out. Instead of getting on a wedding car, they boarded a French tank that stopped by the Mường Thanh bridge and then had a souvenir photo." Nguyễn Ngọc Toản - Wife of Major General Cao Văn Khánh)

Wedding photo of Lieutenant General Cao Văn Khánh and his wife, Professor and Doctor Nguyễn Thị Ngọc was taken on a tank, May 22, 1954