Abstract: Basalt fibers (BF) were modified by physical coating method with three different surfactants. The surface functional groups, hydrophilicity and micro-morphology of raw BF and as-prepared modified basalt fibers (MBF) were characterized by FTIR spectra, optical contact angle analysis and SEM, respectively.Furthermore, the immobilization rate and residual immobilization rate of BF and MBF samples were calculated and biofilm development of BF and MBF were observed by optical microscope and SEM to assess the effects on the immobilization effect of MBF. The results show that the hydrophilicity and dispersion of MBF are efficiently improved in water. Among the modified basalt fibers, the modified basalt fiber modified with hexadecyl trimethyl ammonium chloride (CTAC) (MBF-C) has optimal hydrophilicity and dispersion. The contact angle decreases from 133.57° (BF) to 62.52° (MBF-C). The microorganism immobilization test results illustrate that all three modifications are conductive to increase the microorganism loading and adhesion strength of BF. In addition, the MBF-C possesses an optimal immobilization effect that the immobilization rate and residual immobilization rate reach up to 256.25% and 41.28%, respectively.