John Edwards Leonard (September 22, 1845 – March 15, 1878) was a United States representative from Louisiana.

He was born in Fairville, Pennsylvania, into a Quaker family.

He earned a law degree from Harvard University in 1867.

He studied law in Germany before he returned to the United States; he moved to Louisiana, where he was admitted to the bar in 1870 during the Reconstruction era and commenced practice at Monroe, Louisiana.

In 1876 he was elected as a Republican to the Forty-fifth Congress, serving from March 4, 1877, until his death the following year in Havana, Cuba.