The　magnetic　properties　and　magnetocaloric　effect　of　ferromagnetic　NdCo2　compound　have　been　investigated　around　the　magnetic　phase　transition　using　magnetic　and　heat　capacity　measurements.　The　thermomagnetic　irreversibility　between　the　zero　field-cooled　and　field-cooled　magnetization　curves　is　detected　below　Curie　temperature　in　the　low　magnetic　field,　and　it　is　attributed　to　the　domain　wall　pinning　effect.　The　maximum　magnetic　entropy　change　((δSM)　of　7.33　Jkg-1K-1　and　large　relative　cooling　capacity　of　529.96　Jkg-1　was　obtained　over　the　wide　working　temperature　range　of　78　K　under　magnetic　field　change　of　5　T.　The　corresponding　maximum　adiabatic　temperature　change　(δ　Tad)　is　evaluated　to　be　3.1　K　under　a　same　magnetic　field　change.　Meanwhile,　negligible　thermal　and　magnetic　hysteresis　loss　was　observed　in　paramagnetic　(PM)　to　ferromagnetic　(FM)　transition　region.　Such　a　magnetocaloric　effect　is　attributed　to　a　second-order　magnetostructural　transition　from　a　PM　cubic　phase　to　a　FM　tetragonal　phase　around　the　Curie　temperature　of　Tc　≈　102　K　102　K.　The　observed　magnetocaloric　performance　is　comparable　or　even　better　than　some　earlier　reported　rare-earth　based　Laves　compounds　under　the　same　magnetic　field　change,　implying　that　the　NdCo2　is　one　of　the　potential　refrigerant　material　working　at　low　temperature.　The　critical　exponent　analysis　was　carried　out　to　understand　the　nature　and　underlying　mechanism　of　the　PM　to　FM　phase　transition.　The　critical　exponents　(β,　γ)　obtained　from　modified　Arrott　plots,　the　Kouvel-Fisher　plot,　and　the　critical　isotherm　are　consistent　with　each　other　and　obey　the　Widom　scaling　relation　(δ　=　1+γ/β).　The　values　of　critical　exponents　suggest　that　the　NdCo2　belongs　to　the　three-dimensional-Ising　model　with　short-range　interaction.　The　present　results　may　give　some　clues　for　searching　novel　materials　with　excellent　magnetocaloric　performance　for　refrigeration　technology.　©　2020　IOP　Publishing　Ltd.