The knowledge of the steady-state stress for plastic deformation as a function of temperature and strain rate is essential for hot-forming superconducting material into commercially useful shapes. In this paper, results are presented on the experimental determination of the rheology of fully dense polycrystalline Y1Ba2Cu3O7−x superconducting material at temperatures ranging from 750° to 950°C and strain rates of 10−4, 10−5, and 10−6 s−1. The data are best fitted by a power law: e(s−1)=8.9 × 10−17. (s−1) σ2.5 (Pa) exp [−2.01 × 105(J·mol−1)|RT]. X-ray analysis shows that the superconducting material retains its phase composition after nearly 70% total strain of the sample. A strong anisotropy in the resistivity of the deformed samples is observed because of the development of a preferred orientation of the a or b axis of Y1Ba2Cu3O7−x orthorhombic perovskite single crystals perpendicular to the principal maximum compressive stress.