Semen Isaakovich Dvoirys[1] (Russian: Семён Исаакович Двойрис, romanized: Semyon Isaakovich Dvoyris; born 2 November 1958) is a Russian chess player.

Dvoirys competed in the 1993 Interzonal tournament, held in Biel.

[2] In 2000, he took part in the inaugural Anatoly Karpov International tournament, a category 14 round-robin tournament in Poikovsky, Russia: he scored 3½ points from 9 games, tying for 7th-8th places.

[4] In 2010, he won the Izmailov Memorial tournament in Tomsk,[5] tied for 1st-5th places in the A2 group of the Aeroflot Open with Aleksei Pridorozhni, Igor Glek, Sergey Pavlov and Mikhail Panarin,[6][7] and tied for 1st–4th with Sergei Yudin, Pavel Smirnov and Sergei Iskusnyh at Pavlodar.

This biographical article relating to a Russian chess figure is a stub.