The same question Make an HTTP request with android
Simply, here is the code ( http://www.androidhive.info/2011/10/android-making-http-requests/ ) 
 // Creating HTTP client
        HttpClient httpClient = new DefaultHttpClient();
        // Creating HTTP Post
        HttpPost httpPost = new HttpPost(
                "http://www.example.com/login");
        // Building post parameters
        // key and value pair
        List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>(2);
        nameValuePair.add(new BasicNameValuePair("email", "user@gmail.com"));
        nameValuePair.add(new BasicNameValuePair("message",
                "Hi, trying Android HTTP post!"));
        // Url Encoding the POST parameters
        try {
            httpPost.setEntity(new UrlEncodedFormEntity(nameValuePair));
        } catch (UnsupportedEncodingException e) {
            // writing error to Log
            e.printStackTrace();
        }
        // Making HTTP Request
        try {
            HttpResponse response = httpClient.execute(httpPost);
            // writing response to log
            Log.d("Http Response:", response.toString());
        } catch (ClientProtocolException e) {
            // writing exception to log
            e.printStackTrace();
        } catch (IOException e) {
            // writing exception to log
            e.printStackTrace();
        }