PrRh4.8B2 single crystals were prepared from high temperature copper solutions by slow cooling method, using praseodymium tips, rhodium powders and boron powders as starting materials under helium flow. PrRh4.8B2 belongs to the orthorhombic system with the space group Fmmm; a=0.9697(4)nm, b=0.5577(2)nm and c=2.564(3)nm. Vickers microhardness and electrical resistivity of the compound were measured, and oxidation resistivity of the compound at high temperature in air was studied. Vickers microhardness (HV) and the electrical resistivity (ρ) value on (001) plane with the orthorhombic system of PrRh4.8B2 were in the range of HV=6.12-7.32GPa and ρ=670×10-6Ω·cm, respectively. The oxidation in air of PrRh4.8B2 crystals began to proceed at about 590°C. Weight gain of the sample heated up to 1200°C in air is 13% and the identified oxidation product consisted of the PrBO3 (orthorhombic) and Rh (cubic)
