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This study was conducted to determine humification indices (HIX) by fluorescence spectra of dissolved organic matter (DOM) and solid surface of saline soils, and to decide its correlation with salinity in arid and semi-arid regions. Composite soil samples of different depths (0-20 cm, 20-40 cm and 40-60 cm) were collected from four different halophyte communities along a saline-impact gradient, namely, Comm. Salicornia europaea (CSE), Comm. Suaeda glauca (CSG), Comm. Kalidium foliatum (CKF) and Comm. So-phora alopecuroides (CSA) located around Wuliangsuhai Lake. Fluorescence intensities of fulvic acid peaks at around 350, 380 and 460 nm in synchronous fluorescence spectra increased with rise in salinity, while intensity of protein peak at around 290 nm roughly increased with drop in salinity. HIX showed a good negative correlation with the salinity. The maximum intensity of a UV fulvic acid (peak A) and a visible fulvic acid (peak C) at lambda(240-260)/lambda(415-440) and lambda(320-340)/lambda(415-440) (wavelengths lambda(ex)/lambda(em)) in excitation-emission fluorescence matrices (EEFM), increased with rise in salinity too. There was a close positive relationship between r(A,C) and salinity. HIXSSF, a humification index deduced from solid surface fluorescence spectroscopy in emission mode, showed a strong negative correlation with salinity. The results indicate that the salinity is an important factor to suppress processes soil organic matter humification and plant growth. Since the humification processes are restricted by salinity, HIX can be utilized to be indicative of salinity, especially HIXSSF.