From the end of the 1930s until the early 1960s, Emil Karastoichev was one of the leading Bulgarian chess players. He was multiple times participated in
Bulgarian Chess Championship finals. The best result in these tournaments was in 1950, when he shared 2nd - 3rd place. Emil Karastoichev participated in International Chess Tournaments in
Bucharest (1951) and
Varna (1960). Emil Karastoichev played for Bulgaria first and second team in the
Chess Olympiads: • In 1939, at fourth board in the
8th Chess Olympiad in
Buenos Aires (+3, =3, -3), • In 1962, at second board in the
15th Chess Olympiad in
Varna (+2, =3, -1). Emil Karastoichev played for Bulgaria in the Men's Chess Balkaniads: • In 1946, at eight board in the 1st Men's Chess Balkaniad in
Belgrade (+2, =1, -0) and won team bronze and individual silver medals, • In 1947, at sixth board in the 2nd Men's Chess Balkaniad in
Sofia (+1, =1, -1) and won team bronze and individual bronze medals. At the end of his sports career, Emil Karastoichev worked as a chess trainer at the sports society
Slavia. Among his pupils is one of the strongest chess women's players in Bulgaria, eleven-time champion of the country
Margarita Voiska. ==References==