Piezoelectric responsive molecular ferroelectrics have become a research hotspot due to their advantages of simple fabrication, environmental friendliness, light weight and good mechanical flexibility. Here we proposed a new kind of multipole rare earth molecular ferroelectric, ((nBu)₄N)₃[Ce(NO₃)₄(SCN)₂]((CH₃CH₂CH₂CH₂)₄N = tetrabutylammonium) (1). Compound 1 undergoes a high temperature ferroelectric phase transition at 408 K. It is worth noting that compound 1 has a narrow band gap of 2.61 eV, flexible switchable SHG effect, moderate spontaneous polarization P_s = 3.6 μC cm⁻², and piezoelectric constant = 3 pC N⁻¹. The results show that these findings provide ideas for exploring multifunctional rare earth molecular ferroelectrics with a piezoelectric effect.