We present the measured spin correlation coefficient Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔ for p-Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔHe elastic scattering at 100 MeV at the angles Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔ–Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔ in the center of mass system. The experiment was performed using a 100 MeV polarized proton beam in conjunction with the polarized Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔHe target. Proton beams were injected to the target, and scattered protons were detected by using E-Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔ detectors which consisted of plastic and NaI(Tl) scintillators. The data are compared with rigorous numerical calculations based on realistic NN potentials as well as with the Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔ-isobar excitation . The obtained results indicate that the Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔ expands the knowledge of the nuclear interactions with Cy,y3θc.m.=46.9∘149.2∘3ΔEΔCy,yΔ-isobar or those including 3NFs that are masked in nucleon-deuteron elastic scattering.