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This paper presented the measurement results of space charge distribution and high field conduction in cross-linked polyethylene (XLPE) flat sample at various electric fields for a broad temperature range from 30 to 90℃. The temperature effect on charge trapping and transport mechanism is discussed based on estimation of threshold characteristic and apparent mobility. The time-dependent space charge distributions of XLPE sample for different applied electric fields at various temperatures are shown in Figure 1. The vertical axis represents position, and the horizontal axis represents time. A positive DC field of 10, 20, 30 and 40 kV/mm was applied for 30 min, and 50 kV/mm for 60 min. Then the electrodes were short circuited for 60 min. During voltage applied, both the polarity and amount of space charge accumulated in the sample varies with the electric field at different temperature. The relationship between quasi-steady current density J and applied electric field Eat different temperature is shown in Figure 2. The J-Ecurve shows three distinct regions with different slopes-a gentle region at lower field followed by a steep porr:on in the middle and then a saturation region at higher field. This relationship can be explained by the space-charge-limited current (SCLC) theory.