Crews were called to Wood Row, Hatfield Broad Oak, this morning after reports of a stable fire.
Watch Manager Mark Nevill, Leaden Roding Fire Station, said:
“When we arrived a row of stables and surrounding hedgerow were completely alight.
“Water supplied were difficult, so it was necessary to set up a water shuttle to help us fight the fire.
“Our firefighters worked extremely hard in difficult conditions to bring the fire under control and extinguish it.
“Sadly, four horses died at the scene.”
Firefighters extinguished the fire by 1.55pm.
An investigation into the cause of the fire will take place this afternoon.