The experimental data on thermal properties of multicomponent Al alloys (2007, 2011, 6012, 6082, D16ch and V95pch) are obtained and generalized. The changes in enthalpy are measured by the method of adiabatic drop-calorimetry over the temperature range of 400-1100 K relative to 'base' temperature of Tb=293.15 K. The experimental relations for all alloys are being described well with the computed curves. The main thermodynamic characteristics of alloys in the melting region are defined.