Rotation of a large magnetic field (∼60 kgauss) in a plane perpendicular to the direction of junction current in PbTe tunnel diodes produces a periodic behavior of this current. Diodes in which the junction current flow is along the [100], [110], or [111] crystallographic axis have been investigated. The observed anisotropies are consistent with a crystal with cubic symmetry whose constant energy surfaces inkspace are ellipsoids of revolution oriented along the ⟨111⟩ crystalline axes. The magnetotunneling results are interpreted in terms of the effective motion of each ellipsoidal valley as the magnetic field is increased, valleys oriented at different angles to the electric field contributing with different weights to the tunneling current. Quantitative comparison awaits theory. Heavier mass bands close in energy to these ellipsoids, although unimportant by themselves in tunneling, may be necessary to explain the apparent position of the Fermi level with respect to the band edges. The excess current has the same anisotropy as the tunneling current; however, the thermal current does not show this anisotropy and therefore must be of different origin. Hump current, which was observed in two diodes, disappeared in magnetic fields above 3 kgauss.