Piezoceramics with both high piezoelectric properties and broad temperature usage range are highly in demand for sensor and actuator applications. Unfortunately, the trade-off relationship between two properties poses a significant challenge that remains unresolved. Herein, through combined phase boundary engineering and process engineering, we report the simultaneous achievements of substantially enhanced piezoelectric coefficient d33 (from 784 pC/N to 855 pC/N) and piezoelectric strain d33* (from 620 pm/V to 860 pm/V), and ultrahigh temperature stability (i.e., d33 and d33* change less than 7.3% and 4.6% over 25-175 °C, respectively) in Pb0.92Ba0.08[Zr0.50+xTi0.48-x(Nb0.5Sb0.5)0.02]O3 (x = 0.4) ceramics, superior to those of other typical piezoceramics. The enhanced piezoelectricity and excellent temperature stability are attributed to three synergistic effects, namely, morphotropic phase boundary concomitant with nano-domains, reduced pores, and inhibited oxygen vacancies. Therefore, our proposed strategy provides a new paradigm to boost both piezoelectricity and its temperature stability and is beneficial to both academia and industry. There is a long-standing trade-off between high piezoelectricity and good temperature stability for piezoceramics. Here, authors combine phase boundary engineering and process engineering to relieve this relationship in (Pb, Zr) TiO3 piezoceramics.