An aqueous reduction method was reported for the synthesis of bismuth nanowires (Bi NWs) 5-10 nni in diameter and several micrometers in length under the guidance of PVP molecules. The reactions were performed at 80 degrees C by reducing bismuth chloride with sodium hypophosphite,first in acid and then under neutral cireumstan-Ces. The key to successful preparation of the Bi NWs is, regulation of the reduction speed by control of the pH value. The morphology evolution of the samples was also found to have a strong dependence on the reaction parameter$, including the introduction amount and molecular weight of PVP molecules. A solid-solution-solid (SSS) mechanism was proposed for the nucleation and growth of Bi NWs in our strategy. The as -prepared Bi NWs exhibit excellent visible -light photocatalytic activities for the degradation of the organic pollutant Rhodamine B (RhB) and colorless bisphenol A (BPA). The good recyclability of the Bi NWs on RhB photodegradation 'demonstrates the possibility of their practical.applications,