The Nd0.7Sr0.3MnO3 compounds are treated at a thermal pressure (HTP) of temperature 1273 K and pressure 9 GPa. The results show that the crystal structure and space group of samples keep unchanged while the lattice and structural parameters, especially the microscopic structure change remarkably, which produces significant influence on magnetoelectric transport of the Nd0.7Sr0.3MnO3 ceramic. For electrical transport of the HTP sample, no electroresistance (ER) effect occurs when loaded current is less than 1.5 mA, however, an ER effect around 200% takes place when the loaded current goes up to more than 1.5 mA. Interestingly, the peak at -T curve disappears by replacing a platform, which can return to a peak if a magnetic field is applied again. The formation of intergranular phase and insulating behaviour of sample under thermal pressure condition are suggested to be responsible for the unique transport properties.