To study the precipitation behavior and strengthening effect of (Ti,Mo)C particles, one Cr-MoSsteel with added Ti was austenitized at 880 ℃ and 1350 ℃ followed by oil quenching and tempering. The chemical extraction phase analysis results showed that some (Ti,Mo)C particles were found to have size distributions within the range of 18–36 nm, 36–60 nm, and 60–96 nm when the steel was austenitized at 880 ℃ and particles were precipitated during hot rolling. When the austenitized temperature was 1350 ℃, some new (Ti,Mo)C particles appeared with sizes ranging from 1–5 nm, precipitated during tempering. These (Ti,Mo)C particles demonstrated a distinct secondary hardening platform with a strengthening increment of approximately 165 MPa. The atomic ratio of Ti/Mo in the (Ti,Mo)C particles precipitated during tempering decreased to approximately 1 as the tempering temperature increased.