The Caudron J was essentially a seaplane version of the two-seat Caudron G and single-seat Caudron F. The F, G, and J all followed a similar layout with 2½ bay biplane wings, a tail-unit, with a single fin and rudder, supported on struts attached to the wings at the first inter-plane struts and a central fuselage nacelle housing the cockpit and mounting the tractor engine.

Two main floats were strut-supported under the wings and a small tail-float was attached to the tail-unit.

Power was supplied by a 100 hp (75 kW) Anzani 10-cylinder radial engine.

On 8 May 1914, René Caudron flew the second example from a wooden platform erected over a gun turret, on the French Navy cruiser Foudre.

[2] The first example was powered by a 100 hp (75 kW) Gnome 9 Delta rotary engine, with the remaining two powered by 80 hp (60 kW) Gnome 7 Lambda rotary engines.