Abstract Structural, elastic, and electronic properties of orthorhombic Pbnm CaTiO 3 are studied using both full potential linearized augmented plane wave (FP-LAPW) and plane-wave pseudopotential (PW-PP) methods. Exchange–correlation effects are treated by the generalized gradient approximation (GGA). The equilibrium lattice constants, the bulk modulus, its pressure derivative, and the electronic structure are in good agreement with other calculations and with experimental data. For elastic constants, Young modulus, and Poisson ratio, to our knowledge, no data are available in literature for comparison. In addition, pressure and temperature effects on the volume cell, the bulk modulus, the heat capacity, and the thermal expansion coefficient are investigated in the 0–28 GPa pressure range and in the 0–1200 K temperature range.