The effect of temperature has been investigated on the mechanical properties and fracture behaviour of DP1000 advanced high-strength steel. The variation of the mechanical properties depending on temperature has been determined by performing uniaxial tensile tests at the temperatures of 25, 100, 200, 300 degrees C at the rolling directions of 0 degrees (rolling), 45 degrees (diagonal), and 90 degrees (transverse) at the strain rate of 0.0083 s(-1). The yield strength and tensile strength have showed a slight decrease tendency between 25 and 200 degrees C, but the highest value has been reached by showing an increase at 300 degrees C temperature. The amount of elongation has not been affected significantly with the increase of the temperature. While hardening coefficient has increased due to the rising temperature, no effect has been observed on strength coefficient between 25 and 100 degrees C, but an increase has occurred at higher temperature values.