<p>Ceramic composites of CaTiO₃-Li₂MoO₄ were successfully fabricated using the cold sintering process (CSP), and their microwave dielectric properties were systematically investigated. Densification of CaTiO₃ ceramics typically requires high-temperature sintering above 1200°C, resulting in substantial energy consumption. As the CSP can effectively address these challenges, it has emerged as a transformative low-temperature densification technique, offering both reduced energy consumption and scalable fabrication through relatively simple processing conditions. In the present study, a CaTiO₃-Li₂MoO₄ (with 5–25 wt.% Li₂MoO₄) ceramic composite was prepared, and its phase composition, microstructural evolution, vibrational spectroscopic characteristics, and dielectric properties were systematically examined as a function of water-soluble Li₂MoO₄ content. Notably, a relative densification of <i>ρ</i>_<i>r</i> = 92.4% was achieved at 220°C and 350&#xa0;MPa for 1&#xa0;h, indicating a distinctive densification mechanism governed by a dissolution-precipitation process at ceramic interfaces. The optimized composite exhibits a dense microstructure with strong interfacial bonding and promising microwave dielectric properties of <i>ε</i>_<i>r</i> = 39.7, tan <i>δ</i> = 1.7 × 10⁻³, <i>Q</i>×<i>f</i> = 2557&#xa0;GHz, and <InlineEquation ID="IEq1"> <EquationSource Format="TEX">\(\tau_{f}\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>τ</mi> <mi>f</mi> </msub> </math></EquationSource> </InlineEquation> = +180&#xa0;ppm/°C. These results demonstrate that CSP enables the low-temperature processing of CaTiO₃-Li₂MoO₄ ceramic composites while achieving competitive dielectric performance, making it a promising approach for miniaturized millimeter-wave devices in next-generation electronic systems.</p> Graphical Abstract <p></p>