Aim: To investigate the effect of repair techniques, surface treatment, and repair space design (3 mm space and no repair space) on the transverse, and tensile strengths of repaired denture base. Materials and methods: Four hundred and sixteen samples of two brand heat cured acrylic resin were repaired by four different techniques (water bath, microwave, thermo press, and chemically cured acrylic resin), treated and untreated with monomer, and repaired with 3 mm space, or no space at fracture area. The samples were tested to measure transverse, and tensile strengths, of repaired, and intact (control) samples. Results: Showed that transverse strength of acrylic denture base repaired by chemically cured acrylic resin was significantly lower (P<0.001) than that of water bath, microwave and thermo press. Transverse strength of repaired acrylic denture base was significantly improved (P<0.001) by monomer surface treatment for 180 seconds, and no space repair design showed the lowest transverse strength compared to 3 mm space repair design. The tensile strength of acrylic denture base repaired by microwave was significantly higher than that of water bath, thermo press, and chemically cured acrylic resin. Acrylic denture base treated with monomer for 180 seconds showed the highest tensile strength compared to untreated acrylic denture base. Conclusion: Acrylic denture base with 3 mm space and treated with monomer that repaired with microwave and water bath techniques were better than other techniques. The samples repaired by chemically cured acrylic resin without surface treatment showed significantly the lowest mean tensile strength. And microwave repairing technique was more time saving and more clean process than water bath technique.