Ostrovsky or Ostrovskoy (masculine), Ostrovskaya (feminine), or Ostrovskoye (neuter) may refer to:
- People
- Alexander Ostrovsky (1823–1886), Russian dramatist
- Arkady (Avraam) Ostrovsky (1914–1967), Soviet composer
- Baruch Ostrovsky (1890–1960), first mayor of Ra'anana, Israel
- Erika Ostrovsky, American writer
- Grigory Ostrovsky, Russian painter
- Leonid Ostrovsky (1936-2001), Soviet football star
- Mikhail Ostrovsky, several people
- Nikolai Ostrovsky (1904–1936), Russian Soviet writer, author of the novel How the Steel Was Tempered
- Rafail Ostrovsky (born 1963), professor of computer science and mathematics at UCLA
- Victor Ostrovsky (born 1949), Canadian-born, Israel-raised self-proclaimed former Mossad officer and author of several books
- Places
- Ostrovsky District, name of several districts in Russia
- Ostrovsky (inhabited locality) (Ostrovskaya, Ostrovskoye), name of several rural localities in Russia