High Temperature Expansion for the Ising Model on the Penrose Lattice High temperature expansion for ln Z (Z: the partition function in the absence of magnetic field) of the Ising model on the Penrose lattice is discussed. The terms up to the order of w^{8} are derived. To illustrate an extrapolation procedure employed here, the critical compressibility factor Zc and the correlation function C at Tc, for the neighboring spin pair are first treated in the case of twodimensional square lattice. It turns out that the terms up to w^{8 }for ln Z lead to the results within the error of 0.2 ~ 0.30% as compared to exact values. Along the same line, Zc and C (average correlation function) are calculated for the Penrose lattice. The final results are Zc=0. 138+0.002 and C=0.673+0.003. 
