Abstract: We report the physical properties of EuPtIn4 single crystalline platelets grown by the In flux technique. This compound crystallizes in the orthorhombic Cmcm structure with lattice parameters a = 4.542(1) <(A)over dot>, b = 16.955(2) <(A)over dot> and c = 7.389(1) <(A) over dot>. Measurements of magnetic susceptibility, heat capacity, electrical resistivity, and electron spin resonance (ESR) reveal that EuPtIn4 is a metallic Curie-Weiss paramagnet at high temperatures with an effective moment of mu(eff) approximate to 7.8(1) mu(B) due to divalent Eu ions. At low temperatures, antiferromagnetic (AFM) ordering is observed at T-N = 13.3 K followed by a successive anomaly at T* = 12.6 K. In addition, within the magnetic state, a spin-flop transition is observed with H-c similar to 2.5 T at T = 1.8 K when the magnetic held is applied along the ac-plane. In the paramagnetic state, a single divalent Eu2+ Dysonian ESR line with a Korringa relaxation rate of b = 4.1(2) Oe/K is observed. Interestingly, even at high temperatures, both ESR linewidth and electrical resistivity reveal a similar anisotropy. We discuss a possible common microscopic origin for the observed anisotropy in these physical quantities likely associated with an anisotropic magnetic interaction between Eu2+ 4f electrons mediated by conduction electrons Ver menos