This study explores the magnetic properties of YbCo₂ through specific heat measurements, muon spin rotation spectroscopy, and neutron diffraction under external magnetic fields. A magnetic transition anomaly at 0.3 K in specific heat marks the onset of magnetic order, further corroborated by muon spin resonance data. A second anomaly in specific heat observed in an applied magnetic field indicates a field-induced change of magnetic ordering, confirmed by neutron diffraction experiment in magnetic fields. Yb magnetic moments exhibit a collinear ferromagnetic ordering, while Co moments align antiparallel to Yb moments at low magnetic fields. Increasing the external magnetic field, Co moments develop an additional antiferromagnetic component, modifying the overall magnetic structure. The observed magnetic order in low and high magnetic fields is consistently described by the single magnetic space group Imm'a’ and aligns well with theoretical predictions.