We report on low temperature magnetic properties of KEr(MoO4)2 single crystal, which was investigated from 0.28 K to 30 K in magnetic fields up to 6.5 T. Neutron elastic data collected above and below transition temperature TN ≈ 0.95 K suggest that an antiferromagnetic ordering establishes at low temperatures. The magnetic model within the AxCz mode assuming only magnetic moment at erbium atom positions is suggested. Synchrotron experiment in moderate magnetic fields at temperatures above TN explains the origin of observed signal(s) at (0K0) reflection positions, K odd.