He was born in Galaţi, Romania but was brought up in Piteşti and graduated from the Carol Davila University of Medicine and Pharmacy before starting a career in media.
He was approached in 1991 to work as a presenter for Romanian National Television for the youth programme Viața școlii (School Life) and ended up presenting a number of similar shows over the following years including Măseaua de minte (The Wisdom Tooth), Care pe care (loosely translated as Dog Eat Dog), and Veniți cu noi pe programul doi (Join Us on Channel 2), amongst many other shows.
Based in the Education and Science department of Romanian National Television, he worked as a reporter and presenter of the medical awareness programme Sănătate pentru toți (Health for All) where he could put to good use his studies as a doctor.
[15][16] His popularity increased season after season and in 2017 he was a constant presence in reviews published by the acclaimed website cruisecritic.com [17] Despite offers for returning on Romanian television as a presenter and producer, Leonard preferred to appear only as a guest in TV shows produces by different TV channels in Romania: ProTV (“La Maruta”), Canal D (“Teo Show” and “WOWBiz”), Antena Stars (“Agentia VIP”) and TVR2 (“Femei de 10, Barbati de 10”).
[18][19] Having guest presented in a number of shows from 2005 onwards, he started negotiating with the Romanian National Television in late 2006 regarding his return to the TV screens in 2007.
[30][31] He also began presenting Ro Air, a new talk show exclusive to TVR International (TVRi), with an original format of being set in an airport, with guests arriving as "passengers" and Leonard Miron acting as their "head steward" helped by two "stewardesses".
[34] He also presented a number of Christmas and New Year specials with Irinis Miricioiu called Hai sa ne intalnim sambata seara (Let's meet on Saturday night).