1) Locate server.xml in {Tomcat installation folder}\ conf \ 2) Find following similar statement
<!-- Define a non-SSL HTTP/1.1 Connector on port 8180 -->
<Connector port="8080" maxHttpHeaderSize="8192"
maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
enableLookups="false" redirectPort="8443" acceptCount="100"
connectionTimeout="20000" disableUploadTimeout="true" />
For example
<Connector port="8181" protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="8443" />
Edit and save the server.xml file. Restart Tomcat. Done
Further reference: http://www.mkyong.com/tomcat/how-to-change-tomcat-default-port/