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Nano-zero valent iron (NZVI) has been used toremove several contaminants in groundwater. The presence of natural organicmatter (NOM) in groundwater could play an important role to NZVI performance.In the past, most studies have been focused only on the interaction betweenhumic acid (HA) and nano-zero valent iron or NZVI. However, NOM isheterogeneous and can be classified to 6 fractions based on polarity andcharges including hydrophobic acid (HPOA), hydrophobic base (HPOB), hydrophobicneutral (HPON), hydrophilic acid (HPIA), hydrophilic base (HPIB), andhydrophilic neutral (HPIN). To apply NZVI for in situ groundwater remediation,it is necessary to understand all the effects of other kinds of NOM fractions.The study aims to observe the interaction between NOM surrogate compounds(representing each NOM fraction) and NZVI. Humic acid (HPOA) has the highestinteraction with NZVI base on disappearance of dissolved organic carbon (DOC)with time. This might be due to adsorption of NOM onto NZVI surface. However,the DOC results of other NOM surrogates ((L-tryptophan, HPON, (Aniline, HPOB),(Oxalic acid, HPIA), (L-asparagine, HPIB), (D-xylose, HPIN)) were relativelystable with time.  Adsorptionisotherm experiments were conducted for HPOA and HPIA fractions. Langmuir isotherms fitted with both fractions. This indicates that interaction between HPOA and HPIAfractions with NZVI to be monolayer adsorption on specific sites.