Can you add <code>...</code> tags around the input data from results.bat? That would be very helpful. I cannot tell what goes on each input line.

Modify my DATA section below with the correct formatting.
I made some assumptions about what the data looked like. I took out all of these chomp() statements as they are not necessary. Note that .* in a regex matches all characters except new line's. Also note that chomp @lines; is actually a foreach loop - don't do that if you are going to process each line individually again.

#!/usr/bin/perl
use strict;
use warnings;

my ($sname,$result);

#my $cmd ="results.bat";
my @lines = <DATA>;
#print "@lines\n";
#chomp (@lines);
        foreach my $line(@lines){
      #  chomp ($line);
                if ($line =~ m/Student\sName\s+=\s(.*)/i){
       #         chomp ($1);
                $sname =$1;
                print "$sname ";  #changed
                }
                if ($line =~ m/Exam\sStatus\s+=\s(.*)/i){
      #          chomp ($1);
                $result =$1;
                print "$result "; #changed
                }
     } 
print "\n";
=Prints:
Harry  PASSED  Mike  PASSED  Tom  PASSED  
=cut

__DATA__
 Student Name = Harry 
 Student Code = student_id_1 
 Exam Status = PASSED 
 ------------------------------------- 
 Student Name = Mike 
 Student Code = student_id_2 
 Exam Status = PASSED 
 ------------------------------------- 
 Student Name = Tom 
 Student Code = student_id_3 
 Exam Status = PASSED 
 -------------------------------------
[download]

I just made a small change to your print statement. I would have some other suggestions for you, but let's get the problem statement completely defined first. Your code although somewhat awkward basically "works".

Update:
I noticed that my DATA segment has some trailing spaces. That is probably not true of your actual input file. However a slight regex modification can handle this situation - a "minimal match" upon (.*) that allows for trailing blanks to be deleted. Here is some code for your consideration...

#!/usr/bin/perl
use strict;
use warnings;

while (my $line = <DATA>)
{
   print "$1 " if $line =~ m/Student Name\s*=\s*(.*?)\s*$/; #deletes t
+railing spaces
   print "$1 " if $line =~ m/Exam Status\s*=\s*(.*?)\s*$/;  #deletes t
+railing spaces
}
print "\n";

=Prints:
Harry PASSED Mike PASSED Tom PASSED Bob Smith FAILED 
=cut

__DATA__
 Student Name = Harry    
 Student Code = student_id_1
 Exam Status = PASSED
 ------------------------------------- 
 Student Name = Mike
 Student Code = student_id_2
 Exam Status = PASSED
 ------------------------------------- 
 Student Name = Tom
 Student Code = student_id_3
 Exam Status = PASSED
 ------------------------------------- 
 Student Name = Bob Smith   
 Student Code = student_id_4
 Exam Status=FAILED
[download]

I can tell that you are very new to Perl. That is fine. And this is a good place to go. There is a limit to what can be conveyed in a single thread. If you read and learn more about chomp then I consider this instructional exercise a success.