Novel cinnamic-acid-derived H-bonded liquid crystals with enantiotropic BP*s were facilely prepared. When simply modifying the donor–acceptor ratio, the proportion of (S)-4-(2-octanyloxy) cinnamic acid to 4-(4-propylcyclohexyl) phenyl isonicotinate, the generated BP temperature ranges were consequentially extended with the widest range of about 10 °C, which is seldom found in enantiotropic BP materials. The optimized results of density-functional-theory calculations show that cinnamic-acid-derived mesogens have a bent shape and thus could be beneficial to stabilize enantiotropic blue phases.