In 1955 his family moved south to Daytona Beach, Florida. LeBlanc spent his summers on the beach surfing until he met some teens that played guitars. He later landed a job washing dishes to pay for his first bass guitar. During the next three years of school Lenny played at dances and local clubs around Daytona, developing his vocal talents as well. He graduated from high school in 1969 and moved to Cincinnati, Ohio in 1970. He has resided in Florence, Alabama since 1973.
With much success as a background musician and singer, Lenny LeBlanc embarked on a solo career. In 1975, he recorded a demo and producer Pete Carr sent a copy to Jerry Wexler at Atlantic Records. A few months later Lenny's first solo LP was released. Atlantic saw great potential in Lenny and teamed him with Pete Carr. The result was three chart singles, including the top 15 hit "Falling". The single peaked at No. 13 on the Billboard Hot 100, staying on the chart for 27 weeks during 1977 and 1978. It also reached No. 11 on Billboard's Adult Contemporary chart. LeBlanc and Carr began touring with major acts. After a while Carr decided he enjoyed making the records more than promoting them so the duo went their separate ways. LeBlanc continued writing songs and pursuing a solo effort, this time with Capitol Records.
In 1980, LeBlanc became a born-again Christian and began recording Christian-themed music. In 1983, Heartland Records released Say a Prayer followed by Person to Person in 1984. In 1987, LeBlanc opened his own recording studio in Muscle Shoals, Alabama where he does his own productions as well as others.