When genes encoding three kinds of proteins constituting fibrinogen, an α chain (or variant of α chain), a β chain and a γ chain (or variant of γ chain) are incorporated into an animal cell, a constitutional ratio of respective genes is such that a α chain (and/or variant of γ chain) gene is an equal amount to a 1000-fold amount relative to an α chain (and/or variant of α chain) gene and a β chain gene and, further, by using a baculovirus P35 gene, a recombinant fibrinogen highly producing cell is prepared.