/*  
 * Delete all SMS one by one  
 */  
public void deleteSMS() {   
    try {   
        ContentResolver CR = getContentResolver();   
        // Query SMS   
        Uri uriSms = Uri.parse("content://sms/sent");   
        Cursor c = CR.query(uriSms,   
                new String[] { "_id", "thread_id" }, null, null, null);   
        if (null != c && c.moveToFirst()) {   
            do {   
                // Delete SMS   
                long threadId = c.getLong(1);   
                CR.delete(Uri.parse("content://sms/conversations/" + threadId),   
                        null, null);   
                Log.d("deleteSMS", "threadId:: "+threadId);   
            } while (c.moveToNext());   
        }   
    } catch (Exception e) {   
        // TODO: handle exception   
        Log.d("deleteSMS", "Exception:: " + e);   
    }   
}  
 /*
  * Delete all SMS one by one
  */
 public void deleteSMS() {
  try {
   ContentResolver CR = getContentResolver();
   // Query SMS
   Uri uriSms = Uri.parse("content://sms/sent");
   Cursor c = CR.query(uriSms,
     new String[] { "_id", "thread_id" }, null, null, null);
   if (null != c && c.moveToFirst()) {
    do {
     // Delete SMS
     long threadId = c.getLong(1);
     CR.delete(Uri.parse("content://sms/conversations/" + threadId),
       null, null);
     Log.d("deleteSMS", "threadId:: "+threadId);
    } while (c.moveToNext());
   }
  } catch (Exception e) {
   // TODO: handle exception
   Log.d("deleteSMS", "Exception:: " + e);
  }
 }

<uses-permission Android:name="android.permission.READ_SMS" />  
<uses-permission android:name="android.permission.WRITE_SMS" />