Tigst Assefa Tessema (Amharic: ትእግስት አሰፋ; Oromo: Tigist Asaffaa Tasammaa; born 3 December 1996)[3] is an Ethiopian long-distance runner and the former world record holder in the women's marathon.

She finished fourth at the senior African Championships the following year, and then represented Ethiopia in the event at the 2016 Rio Olympics aged 19.

Her world record has since been broken by Ruth Chepng'etich, who ran 2 hours 9 minutes and 56 seconds at the 2024 Chicago Marathon on 13 October.

The 15-year-old represented that year Ethiopia in the 400 m at the senior African Championships in Athletics in Porto-Novo, Benin, setting a new personal best in the heats with a time of 54.05 s.[3] After 2012, she has never raced a non-relay 400 m again, shifting to twice the distance.

[3] In 2016, still 19, Tigst represented Ethiopia in the 800 metres at the World Indoor Championships held in Portland, United States and at the Rio Olympic Games in Brazil, although failing to advance past preliminary rounds both in the first and second event; she won the race at the Seiko Golden Grand Prix meet in Japan in between.

[3] On 24 September, wearing so-called super shoes, Tigst competed again at the Berlin Marathon and set a new female world record with a landmark time of two hours 11 minutes and 53 seconds, chopping two minutes and eleven seconds from Kenya's Brigid Kosgei's standard of 2:14:04 which had been set at the 2019 Chicago Marathon.

Tigst averaged 3:07.5 min/km pace for the full 42.195-kilometre distance and beat the runner-up by almost six minutes, with the assistance of the male pacemaker Girmay Birhanu Gebru for almost the entire race.

In the final sprint, Tigst appeared to impede her opponent by drifting towards the barriers, resulting in a collision and causing both athletes to stumble.