Chern-Simons theories on the noncommutative plane

We investigate U(N) Chern-Simons theories on the noncommutative plane. We show that for the theories to be consistent quantum mechanically, the coefficient of the Chern-Simons term should be quantized kappa = n/2 pi with an integer n. This is a surprise for the U(1) gauge theory. When uni form background charge density rho (e) is present, the quantization rule changes to kappa + rho (e)theta = n/2 pi with the noncommutative parameter theta. With the exact expression for the angular momentum, we argue in the U(1) theory that charged particles in the symmetric phase carry fractional spin 1/2n and vortices in the broken phase carry half-integer or integer spin -n/2.