diff --git a/app/views/courses/search_not_students.js.erb b/app/views/courses/search_not_students.js.erb
index e7c3fb01f..b6c3cc65a 100644
--- a/app/views/courses/search_not_students.js.erb
+++ b/app/views/courses/search_not_students.js.erb
@@ -1,6 +1,7 @@
 <% if params[:is_observe] %>
 $("#search_not_students_list").html("<%= j(render :partial => 'courses/settings/search_not_students_list') %>");
 <% else %>
+laststSearchCondition = '';
 var htmlvalue = "<%= j(render :partial => 'courses/settings/add_students') %>";
 pop_box_new(htmlvalue, 440, 490);
 <% end %>
\ No newline at end of file