We propose a study of magnetic structures in novel CePtIn4 which extends the family of indium rich cerium ternary compounds. CePtIn4 is one of the RTIn4 compounds (R=Ce, Eu, T= Co, Ni, Pt, Pd) adopting the orthorhombic YNiAl4-type structure (Cmcm) with rather prolongated b-axis. Compounds from this group are in focus due to its potential use in thermoelectric refrigeration [1] or posiblycylindrical Fermi surface (resulting from the prolongated b-axis).Recently, we succeed in preparation of single crystal novel compound CePtIn4 and characterized it by x-ray diffraction and measurement of bulk properties. The compound orders antiferromagnetically below 2.3K, having an order-to-order transition at 1K. Application of magnetic field below the ordering transition leads to appearance of the field induced transition in low fields, most notably for the field applied along the b-axis.The goal of the proposed experiment is to clarify the magnetic structure at the miscroscopical level, potentially sheding light on the ordering within the whole (Ce, Eu)TIn4 group of compounds (showing similar bulk properties at low temperatures).