Luminescence fibers of Eu3+ doped ZnO-MgO-La2O3-B2O3 were prepared by solid state reaction at high temperatures. Their diameters were in the range of 0.01 mm~0.30 mm and their lengths were more than 10 m. Their curves of stress-strain were measured by the axial extension test. The change of the yield surface and the constitutive relations of the stress-strain were investigated based on the theory of elastic-brittle-plastic. Their elastic modulus, intensity, stress peak load, strain of stress intensity, elongation ratio to rupture of the axial extension, and brittleness index of the material were calculated. It is found that their strong emission band of Eu3+ with a maximum at 614 nm belongs to the electric dipole transition of 5D0-7F2 and the emission at 581 nm with 40% relative intensity to 614 nm belongs to magnetic dipole transition of 5D0-7F1. The host emission peak presenting to 438 nm overlaps its excitation band. The result shows that their elastic modulus are higher than those of common glass and marble, close to hard aluminum alloy and rolled aluminum. Their stress intensity and peak load are relatively big.