A study is made of the magnetic state of compounds of the system Ho1-xYxCo2 based on measurement of the electrical resistivity, magnetization and neutron diffraction. The critical concentration is found to be xcr = 0.58. The value of the critical field of the metamagnetic transition is estimated from the value of xcr. It is concluded that long-range ferrimagnetic order is destroyed with change of yttrium concentration by means of a first-order phase transition.