  In the weak disordered regime we provide analytical expressions for the
electron localization lengths in quasi-one dimensional (Q1D) disordered quantum
wire with hard wall and periodic boundary conditions. They are exact up to
order $W^2$ ($W$ being the disorder strength) for an arbitrary number of
channels. Detailed numerical analysis of the Anderson localization, based on
Kubo's formula for conductivity, show excellent agreement with analytical
calculations. We establish relationship between various lengths in Q1D systems.
