A novel, fluorinated diamine monomer with the ether–ketone group, 4,4′-bis(4-amino-2-trifluoromethylphenoxy)benzophenone (2), was prepared from 2-chloro-5-nitrobenzotrifluoride and 4,4′-dihydroxybenzophenone. Flourinated polyimides 5a–f and copolyimides (co-PIs) 5c/a–f were synthesized from 2 and various commercial aromatic dianhydrides via thermal or chemical imidization. Polyimides 5a–f had inherent viscosities ranging from 0.72 to 1.22 dL/g. Besides the chemical imidization of 5c(C), the 5(C) series were soluble in amide-type solvents and even in less polar solvents, but polyimides 5a–f prepared via thermal imidization were insoluble. In comparison of the polyimide 5 series with the analogous non-fluorinated polyimides 6 series based on 4,4′-bis(4-aminophenoxy)benzophenone, the 5 series revealed better solubility, lower color intensity, dielectric constant, and moisture absorption.