Proximity-induced superconductivity in a ferromagnet can induce Cooper pairs with a finite center-of-mass momentum and stabilize Josephson junctions (JJs) with πphase difference in superconductor-ferromagnet-superconductor heterostructures. The emergence of two-dimensional layered superconducting and magnetic materials promises a new platform for realizing πJJs with atomically sharp interfaces. Here we demonstrate a thickness-driven 0-πtransition in JJs made of NbSe2(an Ising superconductor) and Cr2Ge2Te6(a ferromagnetic semiconductor). By systematically increasing the Cr2Ge2Te6weak link thickness, we observe a vanishing supercurrent at a critical thickness of ∼8 nm, followed by a re-entrant supercurrent. Near the critical thickness, we further observe unusual supercurrent interference patterns with vanishing critical current around zero in-plane magnetic field. They signify the formation of 0-πJJs (with both 0 and πregions), likely induced by the nanoscale magnetic domains in Cr2Ge2Te6 © 2022 American Chemical Society. All rights reserved.