Abstarct: In this thesis, experimental study on the critical buckling load of aluminum columns reinforced with glass/epoxy composite belts containing carbon nanotubes (CNTs) are presented. The columns with solid circular cross section are subjected to axially pressure load. Aluminum column specimens reinforced with glass/epoxy and CNT/glass/epoxy are fabricated. CNTs with 0.25, 0.5 and 1 weight percent (wt.%) are dispersed into the epoxy resin. Three laxyers composite belts are wrapped around the column. Glass fibers are placed along the column axes in each laxyer. The columns are tested under fix ended boundary conditions utilizing Instron hydraulic universal testing machine. Pressure load with respect to the end shortening are plotted for each specimen. To achieve the average value of critical buckling load, four specimens are examined for each composite belt material. Results show that when 0.5%CNT/glass/epoxy composite belt is used to reinforce the column, the critical buckling load of the column increases by 50% with respect to the column with glass/epoxy composite belt. The proper dispersion of CNTs into the matrix material along with appropriate adhesion between the nanocomposite belt and the aluminum column lead to the increase of buckling load. Furthermore, to validate the results, buckling analysis of aluminum column reinforced with glass/epoxy composite belt was done in Abaqus finite element software. Finite element simulation confirms the experimental results obtained.