Use -activebackground and -activeforeground: 

#!/usr/bin/perl

use Tk;
my $mw = MainWindow -> new;
my $ck = $mw -> Checkbutton(
    -activebackground => 'gray',
    -activeforeground => 'black',
    -background => 'gray',
    -foreground => 'black',
    -text => 'Tic me',
)->pack;

MainLoop;

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In reply to Re: Background Color - Tk Checkbutton by shmem
in thread Background Color - Tk Checkbutton by Bintuch

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