Before installing the plugin make sure that you're using:

• JIRA 5 or higher
• TeamCity 6.x or higher.

First, you will need to configure your TeamCity instance:

1. Make sure that Rest API Plugin is enabled. To do that go to the following URL: <your-teamcity-server>/httpAuth/app/rest/application.wadl. You should see the output as shown below
   

2. Configure integration with JIRA as described here. 

   If you want to provide TeamCity with access to all JIRA projects, click the Get All Projects link in the window Create New Issue Tracker Connection. Otherwise, specify the projects you want to grant access to in the Project Keys field as shown below. The JIRA user specified in the Username field should have access to relevant JIRA projects.

   

3. Assign the  Project Viewer  and  Agent Manager  roles to an existing TeamCity user 
    or  
   first create a new user and assign the roles.