[5] He was killed in action in the early morning hours of 23 April 1951 in the Battle of Yultong during a successful counterattack against Chinese forces that overran his hilltop position in territory which currently belongs to South Korea.

[9] Yap was conferred the Philippine Medal of Valor by Elpidio Quirino[10] and the United States Distinguished Service Cross for his actions at the Battle of Yultong.

"By direction of the President, pursuant to paragraph 2a, Section I, AFPR 600–45, this Headquarters, dated 16 December 1948, the Medal for Valor is hereby posthumously awarded by the Chief of Staff, Armed Forces of the Philippines, to the following-named officer: CAPT CONRADO D YAP PA O-1914 Coast Artillery Corps AFP For conspicuous gallantry and intrepidity at the risk of his life against overwhelming enemy forces at Yultong, North Korea on 22–23 April 1951.

As Commanding Officer of the Tank Company, Tenth Battalion Combat Team, Philippine Expeditionary Force to Korea, CAPT YAP at 2300 hours on 22 Apr 1951, was executing a defensive action as an advance element of the frontline defense of the United States Army when an overwhelming superior enemy forces assaulted the PEFTOK positions as a part of the enemy’s general offensive.

"[3] "The President of the United States of America, under the provisions of the Act of Congress approved July 9, 1918, takes pride in presenting the Distinguished Service Cross (Posthumously) to Captain Conrado D. Yap, Army of the Philippines, for extraordinary heroism in connection with military operations against an armed enemy of the United Nations while serving with the Tenth Battalion Combat Team, Philippine Expeditionary force to Korea, in action against enemy forces at Yultong, Korea on 22 and 23 April 1951.

Overwhelming enemy strength and heavy fire received from flanks and to the front notwithstanding, they relentlessly pressed the assault, regained the hill, evacuated the casualties, and rescued the isolated unit.

Observing a stricken soldier on the slope of the hill, Captain Yap immediately started toward the man but was mortally wounded by a burst of enemy fire.