[en] The magnetic properties and magnetocaloric effect (MCE) in RE₂Cu₂In (RE  =  Er and Tm) compounds and its composite materials have been investigated. A large reversible MCE is observed at around their own Curie temperature of T _C ∼ 39.4 and 31.6 K for Er₂Cu₂In and Tm₂Cu₂In, respectively. Under a magnetic field change of 0–7 T, the maximum values of magnetic entropy change ($-<!--\; ???\; -->\mathrm{\Delta <!--\; ??\; -->}{S}_{\text{M}}^{max}$) are estimated to be 18.4 and 18.2 J kg⁻¹ K⁻¹ for Er₂Cu₂In and Tm₂Cu₂In, respectively. A table-like MCE at a temperature of 20–50 K and enhanced refrigerant capacity (RC) are realized in the Er₂Cu₂In–Tm₂Cu₂In composite materials. For magnetic field changes of 0–5 and 0–7 T, the maximum improvements of RC reach 32% (12%) and 28% (14%), in comparison with that of the individual compound Er₂Cu₂In (Tm₂Cu₂In), respectively. The excellent MCE properties make the RE₂Cu₂In composite materials attractive for low-temperature magnetic refrigeration. (paper)