In this work, we have fabricated thin film transistors (TFTs) from a solution-based indium gallium zinc oxide (IGZO) and single-walled carbon nanotube (SWNT) blend by varying SWNT concentration. In order to improve electrical performances of IGZO TFT, SWNTs were used as carrier transport rods. We found out that the saturation field effect mobility (sat) and on/off current ratio varied when the SWNT concentration changed. The concentration of SWNT in the solution is a critical parameter to control the electrical performances of IGZO TFT. The optimized performance of IGZO TFT with 0.04wt.% SWNT concentration is as follows: sat of about 0.11cm2/Vs, an on/off current ratio of 105, threshold voltage (Vth) of -2.5V, and a subthreshold slope (S-factor) of 4.1V/decade.