Y.K  Ajao was born at Iseyin, he started playing music at an early age. After a while, he joined a band in Ibadan and played with the band for some time before he formed his own band, Y.K Ajao, and his professional Brothers Band. Professor Y.K Ajao has played music a good number of times he was among those who did their best to propagate juju music. A widely traveled musician, YK Ajao joined the trendsetters almost immediately when Shina Peters came with ACE. He changed his style and named his new style makossa Superstar. Makosa Superstar which was released on Ogo Oluwakiittan Records was a chartbuster, the record was not his first, he has waxed about three records that did not make much impact as such. They are: Akoni Mamu Gege, Oro NEPA, Makosa Series 1 shot him to the forefront. His music was changed and it immediately fit into the new trend of music played by juju musicians.

Professor Y.K Ajao could be described as one of those who worked relentlessly and who one way or the other championed the course of juju music. a national juju King, YK was crowned by King Sunny Ade during the Cokeson Promotion show in Lagos, in the days juju music was being propagated Y.K has released Makosa Series 2, Vigillante all on Ogo Oluwakiitan records label. A highly successful musician Y.K resides in Ikorodu, Lagos.