$VO_2$ thin films have been prepared on borosilicate glass substrate using alkoxide method to characterize the effects of fabricating factors on thermochromic performance. The gel films formed by spin coating were converted to $V_2O_5$ phase during oxidizing heat-tratment and the $VO_2$ phase were formed by reducing heat-treatement. The thermochromic switching properties of $VO_2$ thin films are strongly affected by the crystal phase and microstructure and those could be controlled by reducing heat-treatment conditions. The ther-mochromic switching characteristics of $VO_2$ thin films synthesized were measured at IR (2.5$mu extrm{m}$) as the transition temperature of $63^{circ}C$ the transition width of $3.6^{circ}C$and the maximum and minimum transmittance of 84% and 14% respectively.