We report the thermal expansion, critical behavior, magnetocaloric effect (MCE), and magnetoresistance ( M R ) on the polycrystalline Mn 1.4Fe 3.6Si 3 compound around the ferromagnetic transition. A large negative volume thermal expansion ( α V ∼ − 20 × 10 − 6 K − 1) is observed across the transition temperature with a strong anisotropic variation of lattice parameters in the a b -plane. The anisotropic magnetoelasticity arises from the competition between magnetic ordering and structural deformation that could be responsible for the large MCE ( Δ S m ≃ − 6 J/Kg K) across the magnetic transition in this compound. The large and negative M R ( ∼ − 3 % in 80 kOe) is also observed at the transition temperature which can be attributed to the suppression of spin disorder. Furthermore, the Rhodes-Wolfarth ratio (RWR ><!-- > --> 1 ) and identical field dependence of M R and MCE isotherms indicate the itinerant character of the 3 d electrons. The critical exponents determined from the analysis of magnetization and MCE are consistent with the quasi-two-dimensional (2D) Ising model with long range exchange interactions that decays as J ( r ) ∼ r − 3.41. This unconventional quasi-2D Ising character with long-range interactions can be ascribed to strong a b -plane anisotropy and the delocalized 3 d electrons in the studied compound.