Leonid Aleksandrovich Portenko (11 October 1896 – 26 May 1972) was a Soviet ornithologist of Ukrainian origin who carried out extensive zoogeographic studies on the birds of the northern and north-eastern Palaearctic region.
He was born in Smila, Ukraine, though most of his career was spent working in, and conducting expeditions from, the ornithological department of the Zoological Institute of the Soviet Academy of Sciences in Leningrad.His publications include:
1939, 1941 – Fauna of the Anadyr area
1954, 1960 – The birds of the USSR
1972–1973 – The birds of the Chukchi Peninsula and Wrangel Island
1973 – Fauna of birds of non-polar parts of the Northern Urals
1975 – The birds of zonal steppes and deserts of Central Asia