Janibek Esimuly ruled in XVII century. He was from Djadik dynasty of Kazakh khans and Esim khan’s eldest son. There are no information about his children in historical sources. According to east book “Bahr al-asrar”, in 1611 when Esim-khan conquered part of Central Asia, he appointed Janibek sultan to be akim of Sagardja city, the main city of six Mā Warāʾan-Nahr domains. There is no exact information about when he started ruling Kazakh Horde. However, we can assume that in 30s of XVII century, after his brother Abylay sultan’s death, Janibek gained the throne. I.V. Erofeeva, academic researcher of Kazakhstan history, pays her attention to Russian language sources, where according to periods of Janibek’s life, he ruled Kazakh Horde, having the title of tsar. This evidences that Janibek became a ruler of Kazakh khanate in 30–40-s of XVII century. According to historical sources, Janibek khan often battled with oirats, posing a significant danger for Kazakh khanate. there is an idea that he died in one of the big battles against oirats (Sultanov, 2001: 222). Janibek included into the list of khans, buried in mausoleum of Khodja Ahmed Yasawi.