Bi_7-x Er _x Ti_4.5W_0.5O₂₁(BTW-BIT-xEr³⁺, x=0.05, 0.10, 0.15, 0.25, 0.35) lead-free piezoelectric ceramics with intergrowth bismuth-layered structure was fabricated via solid phase synthesizing method. While the effect of Er³⁺-doping on their up conversion fluorescence and electrical properties was systemically investigated. The results of XRD and SEM reveal the formation of a single phase with bismuth-layered structure of Bi_7-x Er _x Ti_4.5W_0.5O₂₁ (BTW-BIT-xEr³⁺(x=0.05, 0.10, 0.15, 0.25, 0.35)). Three emissions of two green and one red were observed for all the BTW-BIT-xEr³⁺ products with chemical compositions within the desired range under 980nm light excitation. The three emissions centered at 532 nm, 548 nm and 660 nm, and the intensity ratio of red to green emissions could be adjusted by changing the doping amount of Er³⁺ ions. According to the intensity ratio of 532 nm to 548 nm for BTW-BIT-0.15Er³⁺ in the range of 290~440 K, the temperature sensitivity was fitted and showed the maximum temperature sensitivity of 0.0023 K^-1 at 440 K. The dielectric and impedance of BTW-BIT-xEr³⁺ ceramics were analyzed. The results show that Er³⁺ ions replaced Bi³⁺ ions in the pseudo-perovskite layer, therewith the oxygen vacancy concentration decreases, which may be accounted for the decrease of high-temperature dielectric loss, the raising of activation energy and the enhancement of piezoelectric constant. The BTW-BIT-0.15Er³⁺ ceramic possesses the comprehensive properties: d₃₃=14pC/N, T_c=697℃ and tanδ=0.53%, as well as the optimal photoluminescence and good thermal stability.