An engineer plunged to his death yesterday while inspecting a pedestrian span in The Bronx.

Paul Schisler, 54, from Bridgewater, NJ, fell 100 feet, workers said.

He was part of a Schiavone Construction Co. crew preparing for major renovations to the walkway.

The structure, known as High Bridge, arches over the Harlem River, connecting upper Manhattan and The Bronx.

The married father of two landed on dirt next to Metro-North tracks at around 10:10 a.m., witnesses said.

“I’m trying to figure out how it happened,” one member of the crew said.