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A cyclic free-base porphyrin dimer H 4 -CPD Py (CPD=cyclic porphyrin dimer) linked by butadiyne moieties bearing 4-pyridyl groups self-assembles to form a novel porphyrin nanotube in the crystalline state. The cyclic molecules link together through non-classical C―H···N hydrogen bonds and π―π interactions of the pyridyl groups along the crystallographic a axis. H 4 -CPD Py includes a C 60 molecule in its cavity in solution. In the crystal structure of the inclusion complex (C 60 ⊂H 4 -CPD Py ), the dimer "bites" a C 60 molecule by tilting the porphyrin rings with respect to each other, and there are strong π―π interactions between the porphyrin rings and C 60 . The included C 60 molecules form a zigzag chain along the crystallographic b axis through van der Waals contacts with each other. Femtosecond laser flash photolysis of C 60 ⊂H 4 -CPD Py in the solid state with photoexcitation at 420 nm shows the formation of a completely charge-separated state {H 4 -CPD Py •+ + C 60 •― }, which decays with a lifetime of 470 ps to the ground state. The charge-carrier mobility of the single crystal of C 60 ⊂H 4 -CPD Py was determined by flash photolysis time-resolved microwave conductivity (FP-TRMC) measurements. C 60 ⊂H 4 -CPD Py has an anisotropic charge mobility (Σμ=0.16 and 0.13 cm 2 V ―1 s ―1 ) along the zigzag chain of C 60 (which runs at 45° and parallel to the crystallographic b axis). To construct a photoelectrochemical cell, C 60 ⊂H 4 -CPD Py was deposited onto nanostructured SnO 2 films on a transparent electrode. The solar cell exhibited photovoltaic activity with an incident photon to current conversion efficiency of 17 %.