This paper presents a novel fractional lower order subspace-based method for blindmulti-user detection(FLOSUBD)by defining the fractional lower order output energy(FLOOE),inDS-CDMA communications with impulsive noise which call be modeled as a symmetric alphastable process.And the subspace tracking algorithm based on fractional lower order moment(FLOTA)in alpha stable noise environment is also proposed.The improved performance of theproposed FLOSUBD in the presence of a wide range of impulsive noise environments isdemonstrated via Monte Carlo experiments.And simulations also show the performance advantagesof the FLOSUBD over the traditional subspace.based detector(SUBD)in the presence of mixednoise environments of Gaussian noise and non-Gaussian impulsive noise.