The magnetocaloric effect of LaFe11.7Si1.3 compound was investigated under an external magnetic field up to 9 T. The magnetization changed drastically at the Curie temperature TC under different fields and TC increased with the applied fields. The magnetic entropy change |△SM| vs temperature peak consisted of a spike and a plateau. The spike was a spurious result, while the plateau part resulted from the field-induced itinerant-electron metamagnetic (IEM) transition above Tc, which went up with magnetic fields increasing. The width of the magnetic entropy change increased with magnetic fields at a rate of dL△s/dT～4 K/T.