We use high-resolution angle-resolved photoemission spectroscopy to investigate the electronic structure of the antiferromagnetic heavy fermion compound CePt2In7, which is a member of the CeIn3-derived heavy fermion material family. Weak hybridization among 4f electron states and conduction bands was identified in CePt2In7 at low temperature much weaker than that in the other heavy fermion compounds like CeIrIn5 and CeRhIn5. The Ce 4f spectrum shows fine structures near the Fermi energy, reflecting the crystal electric field splitting of the 4f^1_5/2 and 4f^1_7/2 states. Also, we find that the Fermi surface has a strongly three-dimensional topology, in agreement with density-functional theory calculations.