  We describe the scalar and spinor fields on noncommutative sphere starting
from canonical realizations of the enveloping algebra ${\cal A}={\cal
U}{u(2))}$. The gauge extension of a free spinor model, the Schwinger model on
a noncommutative sphere, is defined and the model is quantized. The
noncommutative version of the model contains only a finite number of dynamical
modes and is non-perturbatively UV-regular. An exact expresion for the chiral
anomaly is found. In the commutative limit the standard formula is recovered.
