if ($string =~/(\w+)(_RVCT)/)
There is no need for the capturing parentheses around _RVCT: 
use warnings;
use strict;

my $string = "Viood_ram_shiva_RVCT22";
if ($string =~ /(\w+)_RVCT/)
{
    print "The file name is $1. ";
}

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In reply to Re^2: Extract Sub String by toolic
in thread Extract Sub String by gvinu4u

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