I have more than 600 svg icons. Each one is separate files not combined, is there a way to change the color of all of it at once in Illustrator. I am using Illustrator CS6 version. is it possible through scripting or action?
SVG files are formatted text documents. They follow a standard which makes them suitable for scripting as you suggest.
If you examine a few of your icon files, you may note common features within all of them or a common configuration which will enable your objective.
For example, you will certainly find stroke = "ffaa33" although the portion inside the quotes will vary from file to file. If all of your icons are the same color, the information inside the quotes will be the same.
From the wiki referencing the standards:
Color Colors can be applied to all visible SVG elements, either directly or via fill, stroke, and other properties. Colors are specified in the same way as in CSS2, i.e. using names like black or blue, in hexadecimal such as #2f0 or #22ff00, in decimal like rgb(255,255,127), or as percentages of the form rgb(100%,100%,50%).