The 23-year-old Kenyan clocked 29:43 to smash through the 30-minute barrier and break her own record of 30:04, also set in the Czech capital, at the Sportisimo Prague Half Marathon on April 1.
The performance marked the fifth world record of the year for Jepkosgei, who broke four --10km, 15km, 20km and the half marathon-- en route to her victory at the Prague Half Marathon.
"I'm really pleased to have won today and managed to break a world record," Jepkosgei said. "The whole race was really tough and I basically had my heart set on a record right from the start which really took it out of me. But I'm really happy to have succeeded."
Running with a designated pacesetter for nearly the entire race, Jepkosgei went on a tear from the gun, reaching the midway point in 14:32, a world best for 5k on the roads.
"Everything was going according to plan from the first kilometres; in fact it couldn't have gone any better. I'm pretty tired right now, but at the same time really satisfied."
Behind her, compatriot Fancy Chemutai was second in 30:06, just two seconds outside of the previous world record for the third fastest time ever. Violah Jepchumba, last year's winner, clocked 30:25 to finish third. (ANI)