Sergey Yevgenyevich Treshchov (Russian: Сергей Евгеньевич Трещёв; born 18 August 1958) is a former cosmonaut of the RSC Energia.

His hobbies include soccer, volleyball, ice hockey, hiking, tennis, music, photography, and video.

His responsibilities included the analysis and planning of cosmonaut activities aboard a space station and their inflight technical training.

His duties also included crew support and training for descent and emergency escape scenarios aboard the Mir space station.

The scientific investigations aimed at studying cold plasma, crystal growth, radiation effects in the space and the human body.

[3] The start of the spacewalk was delayed because of an air leak in the sealed hatches between the Pirs airlock and the Zvezda module.

The problem was easily corrected but took Treshchov and fellow cosmonaut Valery Korzun almost a half-hour to step through the procedures and get ready to go outside.

[4] Wearing Russian Orlan spacesuits Treschov and Korzun installed a frame on the outside of the Zarya module to house components for future spacewalk assembly tasks.