"So can anyone help me to solve this issue?"

As others have already indicated, you haven't provided sufficient information for us to determine the problem. Here's some things you can do:

• Check for pathUtil.pm in each of the five directories that @INC contains. This will confirm its absence; however, if found, check that it hasn't got permissions that prevent Perl from reading it. Show us the output from:

  for i in `perl -e 'print "@INC"'`; do ls -l $i/pathUtil.pm; done
  [download]

• Show us the values of environment variables PERL5LIB & PERL5OPT; if there's no value, still include that information.
• Show us the output from: perl -V
• Tell us how you installed pathUtil.pm: manually from a tarball; via a package manager; with a utility such as cpan, cpanm, etc.
• Show us the first 15-20 lines of pod_check.pl. We'll want to see any shebang line; what pragmata you're using; and, how you're attempting to load pathUtil.pm (if that includes a larger construct, such as a BEGIN block, include that in its entirety).
• Tell us how you're running pod_check.pl. This could be simple like ./pod_check.pl; more involved like /path/to/perl options pod_check.pl; or possibly even using some launcher application.
• Tell us what operating system you're using. You said Linux, but not which one: RedHat? Debian? openSUSE? ...? The O/S version may be important, so include that also.

We may want further details but the above would provide a good starting point for initial investigations. Please ensure all code, data, and output, are enclosed in <code>...</code> tags.

Also note that gathering this sort of information, as part of any troubleshooting exercise, will (surprisingly) often highlight the problem for you. For instance, "Oh look, I'm installing with /path/to/X/bin/cpan but running with /path/to/Y/bin/perl. Oops!".