New low sintering temperature and temperature-stable low-loss ceramics based on Li2TiO3 with lithium zinc borate (LZB) glass and LiZnNbO4 doping have been prepared by the conventional solid-state reaction route. The effect of LZB glass addition on the sinterability, phase purity, microstructure, and microwave dielectric properties of Li2TiO3 ceramics has been investigated. The XRD results suggest the presence of single Li2TiO3 phases for LZB glass-added Li2TiO3 ceramics. The addition of LZB glass can effectively lower the sintering temperature to 900 °C, and does not induce much degradation of the microwave dielectric properties. Typically, the 2.0 wt% LZB glass-added ceramic sintered at 900 °C has better microwave dielectric properties of εr = 23.2, Q × f = 38,909 GHz, and τ f = 30.1 ppm/°C. Meanwhile, LiZnNbO4 compound is selected to tune the temperature coefficient of resonant frequency (τ f ) to near zero. It is found that the 2.0 wt% LZB glass-added Li2TiO3 ceramics with 35 wt% LiZnNbO4 sintered at 925 °C have good microwave dielectric properties of εr = 20.7, Q × f = 19,366 GHz, τ f = −0.5 ppm/°C, which can find applications in microwave devices that require low sintering temperature.