Leonid Osipov (1917-2011) – Professor of Riga the Technical University, Doctor of chemistry (Dr. chem). >>

Maxim Osmidov (Max von Osmidoff; 1879-1952) – an architect. >>

Andrey Osokin (1984) – a pianist. >>

Sergey Osokin (1960) – professor, one of the best Latvian pianists. >>

Yelena (Alyona) Ostapenko (1997) – a tennis player. >>

Leonid S Ostrouchow (1867-1937) – a senior advisor to the Livonia governorate, public and theatrical figure, teacher. >>

Nikolay Ovcharov (1868-1933) – a colonel. >>

Sergey Ovsyukov (1941) – Doctor of Engineering (Dr. sc. ing.), Docent of the Riga Polytechnic Institute (from 1990 – Riga Technical University). >>

Ilga Ozish (1945-2023) – programmer, public figure, well-known human rights activist, one of the founders and long-term member of the Latvian Human Rights Committee. >>

Nikolai Osmidoff (1850-1938) – professor of the Riga Polytechnik Institute, famous specialisn in electrical engineering.  >>