NOVELTY - A covalently linked linear porphyrin polymer has porphyrin metal complexes each substituted with coordinating hetero aromatic ring, as constituting units, and the porphyrin metal complexes being fixed by covalent bonds to each other.    USE - Used as element for efficiently capturing and transferring light energy e.g. in an organic solar cell.    ADVANTAGE - The polymer can stably exist without being influenced by the surrounding environment such as polarity of solvent and be easily produced, even if the degree of polymerization is high.    DETAILED DESCRIPTION - A covalently linked linear porphyrin polymer is of formula (1) which is shown in the attached drawing.    R = group of formula (a);    A, B, D = H, alkyl or aryl;    X = -O-, -S-, =NR101, -CH2- or a single bond;    R101 = H or alkyl;    Y = =0, =S, or 2H;    m = 0-4;    n = 0-6;    Z = 5- or 6-membered, nitrogen-containing, coordinating hetero aromatic ring group;    M = ion of typical metals and transition metals;    Q1 = single bond or linear divalent linking group; and    p1 = at least2.    INDEPENDENT CLAIMS are also included for:    (a) a covalently linked linear porphyrin polymer derivative;    (b) a covalently linked cyclic porphyrin polymer;    (c) a covalently linked cyclic porphyrin polymer derivative;    (d) a coordination-organized linear porphyrin polymer;    (e) bis-porphyrin monomer;    (f) a covalently linked porphyrin dimer;    (g) a covalently linked porphyrin dimer derivative;    (h) a porphyrin metal complex monomer;    (i) a method of producing a covalently linked linear porphyrin polymer of formula (1) comprising subjecting the claimed coordination-organized linear polymer to a cyclization metathesis reaction in the presence of Grubbs catalyst;    (j) a method of producing th claimed covalently linked linear porphyrin derivative comprising hydrogenating a porphyrin in the presence of metal catalyst; oxidizing the porphyrin polymer in the presence of catalyst; or oxidizing the porphyrin polymer, optionally in the presence of catalyst, respectively;    (k) a method of producing the claimed cyclic porphyrin polymer comprising subjecting the coordination-organized cyclic porphyrin polymer to cyclization metathesis reaction in the presence of Grubbs catalyst;    (l) a method of producing coordination-organized linear porphyrin polymer, comprising self-organizing the bis-porphyrin monomer in a non-polar solvent;    (m) a method of producing porphyrin dimer comprising subjecting the coordination-organized porphyrin dimer to cyclization metathesis reaction in the presence of Grubbs catalyst;    (n) a method of producing covalently linked linear porphyrin derivative of formula (6-1) comprising hydrogenating the porphyrin dimer in the presence of metal catalyst; oxidizing the porphyrin dimer in the presence of catalyst; or oxidizing the porphyrin dimer, optionally in the presence of catalyst; and    (o) a method of producing coordination-organized porphyrin dimer comprising self-organizing the porphyrin metal complex monomer in a non-polar solvent.