Objective: To evaluate the surface roughness of different orthodontic wire groups and to detect the microbial colonization level associated with orthodontic wire types. Material and Methods: The samples were distrusted as ten St. Steel orthodontic arch wire, ten non-coated nickel titanium orthodontic arch wire, ten white-coated nickel titanium orthodontic archwire and ten glass fiber reinforced plastic orthodontic arch wire.  Saliva was collected from volunteers with acceptable pH and the cultivated on suitable bacteriological media to isolate and identify the microorganisms. Streptococcus Mutans were isolated and the adherence test was carried out. The observation was categorized either low or moderate or high adherence depending on macroscopic observation. Also, microbial count was done and estimated then profilometer was used to measure surface roughness of the each group. The specimens were photographed using USB Digital microscope by affixed magnification 120 X. The collected data were statistically analyzed using one way ANOVA. Results: The orthodontic St.Steel wire revealed the least amount of surface roughness to all groups. So, the St.Steel wire should poses the least amount of mechanical friction during the sliding mechano- therapy.The esthetic wire group showed less surface roughness when compared to non-esthetic ones. Also, the coated wires revealed less surface roughness and this can be attributed to the covering material as Epoxy resin. Surface roughness of the orthodontic wires could be considered not only the factor controlling microbial colonization but also wire material type, salivary pH and the surrounding hygiene medium.