An intercalation compound of the layered perovskite, K2La2Ti3-O-10, with 5,10,15,20-tetrakis(N-methylpyridinium-4-yl)-21H,23H-porphin (TMPyP4+), as the first example of a large molecule intercalation into this perovskite, was successfully prepared by a guest-exchange method using the n-PrNH3+-HLaTi3O10 intercalation compound as an intermediate. Its structural characterization was carried out by means of X-ray diffraction, UV, and polarized spectroscopic investigations. The porphyrin molecules were revealed to be situated with their molecular planes inclined to the (La2Ti3O10)(2-) layers at an angle of 58 degrees because of the high charge density of the host layers.