It is named in honour of missionary and explorer Paul Le Jeune, one of the founders of the Jesuit mission that was opened in 1634 in nearby Trois-Rivières, Quebec.

The need for this path for forestry was greatly reduced when a railway was completed in 1908 in the nearby Tawachiche sector connecting Hervey-Jonction to La Tuque.

The area is suitable for hunting, fishing, camping, water activities, nature observation and gathering wild fruit.

Missionary Lake is divided into two parts, north and south, which are interconnected by Groleau Strait which is 0.77  km in length.

A bridge spans the strait at its northern portion to serve the cottages located on the northeast shore of the lake.

In Saint-Tite, the École secondaire Paul Le Jeune (High School) which opened in 1969, also pays tribute to the missionary.