Аннотация:We have theoretically explained the obtained data on the Peltier effect in SINIS junction on a ferromagnetic (Fe) substrate. A maximal electron cooling in SINIS structure at phonon temperature 300 mK and below was reached experimentally. Several reasons allowing this achievement are the optimization of geometry, the effective withdrawing of hot quasiparticles from the tunnel barrier using electron traps, and the suppression of Andreev current in hybrid N-island, composed by Fe and Al.