The crystal structure and magnetic properties of TbCo 2 compound have been analyzed by neutron diffraction, at pressures up to 4.1GPa in the temperature range 10–300K. A rhombohedral type structure of R3¯m type is shown below Curie temperature. The distortion degree of structure increases with pressure as well as when lowering temperature. The temperature dependences of terbium and cobalt moments can be described by Brillouin functions. The Curie temperatures decrease linearly with pressure with a slope of dT c /dP=−9K/GPa. The evolution with pressure of the cobalt magnetic moments and Tb5d band polarizations are theoretically analyzed. The experimental data are well described by band structure calculations. The magnetic behavior of cobalt in heavy rare-earth RCo 2 compounds is analyzed in spin fluctuations model. A gradual quenching of spin fluctuations by internal field was shown.