synopsis s an extension of earlier work on the condensation of ferrocene with aldehydes, the ycondensation of ferrocene with p and o-carboxybenzaldehyde is described. While, he former case, regular polycondensation occurs giving rise to a polymer composed of ocenylene and Pcarboxybenzal units, a deviation from this route is observed in the arboxybenzaldehyde case, where a polymer containing both carbaxybenzal qnd 3,3halide bridging units between the ferrocenylene groups is formed instead. This unected behavior can be accounted for by a hydride abstraction mechanism. In supt of the polymer structure proposed, 3-ferrocenylphthalide and 3,3-diferrocenylhalide are isolated as intermediates or by-products. In both polymer series, numberrage molecular weights up to 3000 (unsubfractionated) are measured. The polymers soluble in a number of organic solvents and can be cured with epoxides.