You can use opencsv
for this
Download the library from here:
http://sourceforge.net/projects/opencsv/
In this you can find jar file.
Inside your activity use this:
CSVWriter writer = null;
try
{
writer = new CSVWriter(new FileWriter("/sdcard/myfile.csv"), ',');
String[] entries = "first#second#third".split("#"); // array of your values
writer.writeNext(entries);
writer.close();
}
catch (IOException e)
{
//error
}