| Armenak Alachachian | |
| Birth Date: | 25 December 1930 |
| Birth Place: | Alexandria, Egypt |
| Death Place: | Toronto, Canada |
| Nationality: | Soviet / Russian / Armenian |
| Height Ft: | 5 |
| Height In: | 9.25 |
| Weight Lb: | 165 |
| Career Position: | Point guard |
| Career Number: | 6 |
| Career Start: | 1948 |
| Career End: | 1966 |
| Coach Start: | 1966 |
| Coach End: | 1970 |
| Years1: | 1948–1954 |
| Team1: | SKIF Yerevan |
| Years2: | 1955–1957 |
| Team2: | Burevestnik Almaty |
| Years3: | 1958–1966 |
| Team3: | CSKA Moscow |
| Cyears1: | 1966–1968 |
| Cteam1: | CSKA Moscow (assistant) |
| Cyears2: | 1968–1970 |
| Cteam2: | CSKA Moscow |
| Highlights: | As player:
As head coach:
|
Armenak Misakovich Alachachian (alternate spellings: Alachachyan, Alatchatchan, Alajajian) (Armenian: Արմենակ Միսակի Ալաջաջյան, December 25, 1930 - December 4, 2017) was an Armenian-Soviet basketball player and coach. During his club playing career, the point guard reached European stardom with CSKA Moscow and the senior men's Soviet Union national team. He was the first person to ever win a EuroLeague title, as both a player and a head coach.
Whie he was the team captain, Alachachian helped CSKA Moscow win its first EuroLeague championship in 1961. He added a second EuroLeague championship with CSKA in 1963, and he reached another EuroLerague Final in 1965, before retiring.
As a player of the senior men's Soviet national team, Alachachian won four gold medals at the FIBA EuroBasket. As he won the 1953 EuroBasket, the 1961 EuroBasket, the 1963 EuroBasket, and the 1965 EuroBasket. He also won a Summer Olympic Games silver medal, which he won at the 1964 Tokyo Summer Olympics.
Aleksandar Gomelsky, who was at the time CSKA Moscow's sports director, assigned Alachachian to the club's head coach position in 1968. Alachachian would go on to lead the team to the Euroleague championship in 1969. Alachachian thus became the first person to win the title as both a player and a head coach.