From 1976 to 1980, Yonhy Lescano studied law at the Catholic University of Santa María in Arequipa. From 1984 to 2001, he worked as an independent lawyer in his hown town Puno. Additionally, he was a professor, lecturing law at the National University of the Altiplano (UNA) in Puno, from 1985 to 2001. In 2001, he was elected to the Congress to represent the constituency of Puno, on the list of the centrist Popular Action party. He was re-elected in 2006, on the joint Center Front coalition list, and in 2011, in the constituency of Lima, and on the list of the Possible Peru Alliance, of which his Popular Action is a constituent part. Since 2009, he has been the Popular Action party's national secretary-general.