AbstractMagneto‐quantum transport properties in AlxGa1–xAsySb1–y/InAs deep quantum wells (QWs) with different well width (Lw = 15 and 50 nm) have been studied both in low and high magnetic fields. The low‐field magnetoconductance has been explained in the light of the two‐dimensional weak‐localization theory taking account of the effect of Zeeman splitting on spin‐orbit scattering of electrons. Analysis of Quantum Hall effect (QHE) in high‐field region for Lw = 50 nm indicates the existence of a small number of holes only partially participating with the QHE, suggesting that our QW is a type‐II hetero‐structure. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)