The two-time World Athletics Championships bronze medallist, who finished fourth in the Olympic 5,000m final two months ago, was 25.
A criminal investigation is now underway into her death, with police saying her husband has gone missing.
On Wednesday, crime scene investigators were at the house of Tirop, who police say was reported missing by her father on Tuesday night.
"When [police] got in the house, they found Tirop on the bed and there was a pool of blood on the floor," Tom Makori, head of police for the area, said.
"They saw she had been stabbed in the neck, which led us to believe it was a knife wound, and we believe that is what caused her death.
"Her husband is still at large, and preliminary investigations tell us her husband is a suspect because he cannot be found. Police are trying to find her husband so he can explain what happened to Tirop."
Makori added that police believe that CCTV in the house may be able to help with their investigation.
Tirop was also found dead with a stab wound to her stomach, sources have told the BBC.
Athletic success
"Athletics Kenya are distraught to learn about the untimely death of World 10,000m bronze medallist Agnes Tirop," the country's athletics body said in a statement.
"We are still working to unearth more details surrounding her demise. Kenya has lost a jewel who was one of the fastest-rising athletics giants on the international stage, thanks to her eye-catching performances on the track."
Last month, Tirop set the world record for a women's only 10km road race in Germany.
At the 2020 Olympic Games in August, Tirop finished just outside the medal places for the women's 5,000m, trailing Ethiopia's bronze medallist Gudaf Tsegay by 0.75 seconds.
As well as her 10,000m bronze medals at both the 2017 and 2019 World Athletics Championships, Tirop also impressed off the track.
In September, she set a time of 30 minutes and one second in Herzogenaurach, Germany, as she took 28 seconds off the old 10km road race record set in 2002.
Tirop began her career as a junior athlete in 2011, winning two bronze medal in the 5,000m at that year's world junior championships.
Four years later, during a rapid ascent, she won the senior World Cross Country championships in China - becoming the second youngest medallist at that level.
"It is unsettling, utterly unfortunate and very sad that we've lost a young and promising athlete who, at a young age of 25 years, had brought our country so much glory," Kenya President Uhuru Kenyatta stated.
"It is even more painful that Agnes, a Kenyan hero by all measures, painfully lost her young life through a criminal act perpetuated by selfish and cowardly people."
"I urge our law enforcement agencies to track down and apprehend the criminals responsible for the killing of Agnes so that they can face the full force of the law," added the head of state.