diff --git a/app/views/admin/seminars/_form.html.erb b/app/views/admin/seminars/_form.html.erb
index 43d812b..f6e9605 100644
--- a/app/views/admin/seminars/_form.html.erb
+++ b/app/views/admin/seminars/_form.html.erb
@@ -39,14 +39,14 @@
       <div class="control-group">
         <label class="control-label muted"><%= t('seminar.seminar_start_date') %></label>
         <div class="controls">
-          <%= f.datetime_picker :seminar_start_date, :no_label => true, :format=>"yyyy/MM/dd" %>
+          <%= f.datetime_picker :seminar_start_date, :no_label => true, :format=>"yyyy/MM/dd", :new_record => @seminar.new_record? %>
         </div>
       </div>
 
       <div class="control-group">
         <label class="control-label muted"><%= t('seminar.seminar_end_date') %></label>
         <div class="controls">
-          <%= f.datetime_picker :seminar_end_date, :no_label => true, :format=>"yyyy/MM/dd" %>
+          <%= f.datetime_picker :seminar_end_date, :no_label => true, :format=>"yyyy/MM/dd", :new_record => @seminar.new_record? %>
         </div>
       </div>
 
@@ -72,14 +72,14 @@
       <div class="control-group">
         <label class="control-label muted"><%= t('seminar.signup_start_date') %></label>
         <div class="controls">
-          <%= f.datetime_picker :signup_start_date, :no_label => true, :format=>"yyyy/MM/dd" %>
+          <%= f.datetime_picker :signup_start_date, :no_label => true, :format=>"yyyy/MM/dd", :new_record => @seminar.new_record? %>
         </div>
       </div>
 
       <div class="control-group">
         <label class="control-label muted"><%= t('seminar.signup_end_date') %></label>
         <div class="controls">
-          <%= f.datetime_picker :signup_end_date, :no_label => true, :format=>"yyyy/MM/dd" %>
+          <%= f.datetime_picker :signup_end_date, :no_label => true, :format=>"yyyy/MM/dd", :new_record => @seminar.new_record? %>
         </div>
       </div>
 
@@ -87,14 +87,14 @@
       <div class="control-group">
         <label class="control-label muted"><%= t('seminar.contribute_start_date') %></label>
         <div class="controls">
-          <%= f.datetime_picker :contribute_start_date, :no_label => true, :format=>"yyyy/MM/dd" %>
+          <%= f.datetime_picker :contribute_start_date, :no_label => true, :format=>"yyyy/MM/dd", :new_record => @seminar.new_record? %>
         </div>
       </div>
 
       <div class="control-group">
         <label class="control-label muted"><%= t('seminar.contribute_end_date') %></label>
         <div class="controls">
-          <%= f.datetime_picker :contribute_end_date, :no_label => true, :format=>"yyyy/MM/dd" %>
+          <%= f.datetime_picker :contribute_end_date, :no_label => true, :format=>"yyyy/MM/dd", :new_record => @seminar.new_record? %>
         </div>
       </div>