Abstract: In order to study the axial tensile mechanical properties and damage process of internally cured polyvinyl alcohol fiber (PVA) reinforced concrete specimens at different temperatures, uniaxial compressive and axial tensile tests were carried out to analyze the changing rules of its compressive strength, high temperature mass loss rate, stress-strain curve, etc.; a uniaxial tensile damage constitutive model considering the effect of temperature was established to analyze the trend of the degree of damage, which revealed the damage destruction mechanism of internally cured PVA fiber reinforced concrete at high temperatures. The test results show that: the compressive strength with the PVA fiber dosage shows a trend of increasing and then decreasing, the optimal dosage of PVA fiber is 0.15%, the water release shrinkage of super absorbent resin (SAP) particles and the melting of PVA fibers at high temperature are the main reasons for the loss of specimen quality; with the increase of temperature, the descending section of the stress-strain curve gradually tends to be flat, and there is a short-lived plateau area; The incorporation of PVA fibers can better improve the toughness of concrete; the established damage constitutive model is applicable to internally cured PVA fiber-reinforced concrete, but it still has some limitations and needs to be further improved.