#!/usr/bin/perl use strict; my $file1 = <) { my (@lines) = split; $hash{$lines[5]} = [@lines]; } while () { my (@lines) = split; if ( defined( $hash{$lines[5]} ) && $hash{$lines[5]}->[5] eq $lines[5] ) { print join " ", @{ $hash{$lines[5]} } , "\n"; } else { print; } } __DATA__ 234 13 4 49 + TAT_01 id_nu1 explan1 236 123 3 67 + TAT_02 id_nu2 explan2 534 12 8 13 + TAT_03 id_nu3 explan3 764 124 9 33 + TAT_04 id_nu4 explan4 224 153 2 37 + TAT_05 id_nu5 explan5