How can open add content form in modal form module
finally I found my answer, I put it here for another than want do something like this

function mymodule_menu() {
  $items = array();

  $items['mymodule/page'] = array(
    'page callback' =&gt; 'mymodule_page',
    'access callback' =&gt; TRUE,
    'type' =&gt; MENU_CALLBACK,
  );

  $items['mymodule/%ctools_js'] = array(
    'page callback' =&gt; 'mymodule_callback',
    'page arguments' =&gt; array(1),
    'access callback' =&gt; TRUE,
    'type' =&gt; MENU_CALLBACK,
  );

  return $items;
}


/**
 * Helper function to make a link.
 */
function _mymodule_make_link($link_text = '') {
  // Set a default value if no text in supplied.
  if (empty($link_text)) {
    $link_text = 'Magical Modal';
  }

  return '&lt;div id="magical-modal-link"&gt;' . l($link_text, 'mymodule/nojs', array('attributes' =&gt; array('class' =&gt; 'ctools-use-modal'))) . '&lt;/div&gt;';
}



/**
 * An example page.
 */
function mymodule_page() {
  // Load the modal library and add the modal javascript.
  ctools_include('modal');
  ctools_modal_add_js();
  return _mymodule_make_link('Magical modal');
}



/**
 * Ajax menu callback.
 */
function mymodule_callback($ajax) {
  if ($ajax) {
    ctools_include('ajax');
    ctools_include('modal');

    $form_state = array(
      'ajax' =&gt; TRUE,
      'title' =&gt; t('MyModule Modal Form'),
    );

    // Use ctools to generate ajax instructions for the browser to create
    // a form in a modal popup.
    $output = ctools_modal_form_wrapper('mymodule_form', $form_state);

    // If the form has been submitted, there may be additional instructions
    // such as dismissing the modal popup.
    if (!empty($form_state['ajax_commands'])) {
      $output = $form_state['ajax_commands'];
    }

    // Return the ajax instructions to the browser via ajax_render().
    print ajax_render($output);
    drupal_exit();
  }
  else {
    return drupal_get_form('mymodule_form');
  }
}



/**
 * Drupal form to be put in a modal.
 */
function mymodule_form(&amp;$form, $form_state) {
  module_load_include('inc', 'node', 'node.pages');
$form = node_add('article');
  return $form;
}