Bonjour despekill,
Voici un essai :
Sub Remplacer()
with sheets(2)
dl2 = .Cells(.rows.count, 1).end(xlup).row
t = .range("A1:A" & dl2).value
with sheets(1)
dl1 = .cells(.rows.count, 4).end(xlup).row
for i = 1 to ubound(t)
if application.countif(.range("D1:D" & dl1), t(i, 1)) > 0 then
ligne = application.match(t(i, 1), .range("D1:D" & dl1), 0)
t(i, 1) = .cells(ligne, 1).value
end if
next i
end with
.range("A1:A" & dl2).value = t
end with
end sub
Cdlt,