Karel Hromádka started his ice hockey career playing for HOVS Praha. He had his first appearance in the senior team of the club in 1924. Three years later he moved to the top club LTC Praha. Together with Josef Maleček and Jirí Tožicka, Hromádka formed the legendary line that led the club to five consecutive national titles from 1931-35. With him, LTC won the prestigious Spengler Cup three times, in 1929, 1930 and 1932. In 1941 he joined SK Podolí, where he finished his career in the following year, but he stayed with the club as a coach until 1948. Internationally, the 1928 Olympic Winter Games marked his first appearance. He competed in two European Championships (1929, 1932), winning the title in 1929. He also took part in five World Championships (1930-31, 1933-35), with his best result a bronze medal in 1933. The 1936 Olympic Winter Games were his last international tournament. He played a total of 54 international matches scoring 16 goals. When the Communists took over in Czechoslovakia in 1948, Hromádka emigrated to the United States. He was also an excellent football (soccer) player.