Mortar forms a fundamental constituent of concrete, resulting in similar behavior and drawbacks between them. In this study, we investigate one of these drawbacks (cracks). This study investigates bacterial self-healing efficiency at different temperatures RT (24°C), Zero, and Sub-Zero (-16 ± 2 °C, and – RT, (- 24 °C)), bacteria type, concentration, and percent on self-healing of cracks in cement mortar. The two distinct strains of bacteria were Bacillus Megaterium (BM) and Bacillus Sphaericus (BS), with varying concentrations of 0 %, 1%, and 2.5%. The efficiency of the bacterial strains was evaluated using a variety of techniques, such as compressive and flexural strength tests, energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray diffraction (XRD). It was observed that RT and Zero temperature at 2.5 % of BS or BM had the same behavior for crack-healing efficiency by 100% with an …