Abstract
Assuming the existence of a supersymmetric U(1) gauge factor at the TeV energy scale (motivated either by the superstring-inspired E_6 model or low-energy electroweak phenomenology), several important consequences are presented. The two-doublet Higgs structure at the 100 GeV energy scale is shown to be different from that of the Minimal Supersymmetric Standard Model (MSSM). A new neutral gauge boson Z' corresponding to the extra U(1) mixes with the Z. The supersymmetric scalar quarks and leptons receive new contributions to their masses from the spontaneous breaking of this extra U(1). The assumption of universal soft supersymmetry breaking terms at the grand-unification energy scale implies a connection between the U(1) breaking scale and the ratio of the vacuum expectation values of the two electroweak Higgs doublets.