diff --git a/CHANGELOG b/CHANGELOG
index 3fe057ffd8..23515b52ee 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,4 @@
+* Warn user when posting a statement with cancelled or paid invoices
 * Fill move line's origin with statement line
 
 Version 5.8.0 - 2020-11-02
diff --git a/message.xml b/message.xml
index 511027ccbe..d46ddec636 100644
--- a/message.xml
+++ b/message.xml
@@ -27,6 +27,9 @@ this repository contains the full copyright notices and license terms. -->
         <record model="ir.message" id="msg_statement_delete_cancel">
             <field name="text">To delete statement "%(statement)s" you must cancel it.</field>
         </record>
+        <record model="ir.message" id="msg_statement_invoice_paid_cancelled">
+            <field name="text">The validation of the statements will remove already paid or cancelled invoices from the statements' lines.</field>
+        </record>
         <record model="ir.message" id="msg_statement_paid_invoice_draft">
             <field name="text">The validation of the statements will remove paid invoices from other statements.</field>
         </record>
diff --git a/statement.py b/statement.py
index 742d69f6bb..225fe61260 100644
--- a/statement.py
+++ b/statement.py
@@ -1,5 +1,6 @@
 # This file is part of Tryton.  The COPYRIGHT file at the top level of
 # this repository contains the full copyright notices and license terms.
+import hashlib
 from decimal import Decimal
 from collections import namedtuple, defaultdict
 from itertools import groupby
@@ -499,9 +500,23 @@ class Statement(Workflow, ModelSQL, ModelView):
         pool = Pool()
         Line = pool.get('account.statement.line')
         Warning = pool.get('res.user.warning')
-
+        paid_cancelled_invoice_lines = []
         for statement in statements:
             getattr(statement, 'validate_%s' % statement.validation)()
+            paid_cancelled_invoice_lines.extend(l for l in statement.lines
+                if l.invoice and l.invoice.state in {'cancelled', 'paid'})
+
+        if paid_cancelled_invoice_lines:
+            warning_key = ('%s.statement_paid_cancelled_invoice_lines' %
+                    hashlib.md5(str(paid_cancelled_invoice_lines).encode(
+                        'utf-8')).hexdigest())
+            if Warning.check(warning_key):
+                raise StatementValidateWarning(warning_key,
+                    gettext('account_statement'
+                        '.msg_statement_invoice_paid_cancelled'))
+            Line.write(paid_cancelled_invoice_lines, {
+                    'invoice': None,
+                    })
 
         cls.create_move(statements)