If I understand your question correctly, the problem isn't with your s///, it's with your initialisation of $value. It should be single-quoted, not double. 
my $value = 'sample1\*sample2\*sample3*sample4*sample5';
$value =~ s#\*#STAR#g;
print $value

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Output: 

sample1\STARsample2\STARsample3STARsample4STARsample5

[download]

In reply to Re: Regex problem by FunkyMonk
in thread Regex problem by siraj

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