If you set your data to an anonymous hash, you can adjust it as required. 
$tree->add('1.1',-text=>'aaa',-data=>{-info=>'aaa'});

[download]
then 
# get data
my $d=$tree->infoData('1.1');

# change data
$d->{-info}='new data';

[download]
Next time you get the infoData, it will have your new information.

UPDATE!

or you can use entryconfigure 

# set entry
$tree->add('1.1',-text=>'aaa',-data=>'aaa');

# change data for entry
$tree->entryconfigure('1.1',-data=>'new data');

[download]

In reply to Re: how to change Tk::Tree data value by Sandy
in thread how to change Tk::Tree data value by hxdhan

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