diff --git a/CHANGES b/CHANGES
index 95a2e1906ee..18fb2ce6ed7 100644
--- a/CHANGES
+++ b/CHANGES
@@ -16,6 +16,8 @@ Incompatible changes
   :confval:`autosummary_generate_overwrite` to change the behavior
 * #5923: autodoc: the members of ``object`` class are not documented by default
   when ``:inherited-members:`` and ``:special-members:`` are given.
+* #6417: py domain: doctree of desc_parameterlist has been changed.  The
+  argument names, annotations and default values are wrapped with inline node
 
 Deprecated
 ----------
@@ -31,6 +33,7 @@ Features added
   not to document inherited members of the class and uppers
 * #6558: glossary: emit a warning for duplicated glossary entry
 * #6558: std domain: emit a warning for duplicated generic objects
+* #6417: py domain: Allow to make a style for arguments of functions and methods
 
 Bugs fixed
 ----------
diff --git a/sphinx/domains/python.py b/sphinx/domains/python.py
index f23c5025614..6603ebefd65 100644
--- a/sphinx/domains/python.py
+++ b/sphinx/domains/python.py
@@ -30,6 +30,7 @@
 from sphinx.util import logging
 from sphinx.util.docfields import Field, GroupedField, TypedField
 from sphinx.util.docutils import SphinxDirective
+from sphinx.util.inspect import signature_from_str
 from sphinx.util.nodes import make_refnode
 from sphinx.util.typing import TextlikeNode
 
@@ -62,6 +63,34 @@
 }
 
 
+def _parse_arglist(arglist: str) -> addnodes.desc_parameterlist:
+    """Parse a list of arguments using python parser"""
+    params = addnodes.desc_parameterlist(arglist)
+    sig = signature_from_str('(%s)' % arglist)
+    for param in sig.parameters.values():
+        node = addnodes.desc_parameter()
+        if param.kind == param.VAR_POSITIONAL:
+            node += nodes.inline('', '*' + param.name, classes=['argument'])
+        elif param.kind == param.VAR_KEYWORD:
+            node += nodes.inline('', '**' + param.name, classes=['argument'])
+        else:
+            node += nodes.inline('', param.name, classes=['argument'])
+
+        if param.annotation is not param.empty:
+            node += nodes.Text(': ')
+            node += nodes.inline('', param.annotation, classes=['annotation'])
+        if param.default is not param.empty:
+            if param.annotation is not param.empty:
+                node += nodes.Text(' = ')
+            else:
+                node += nodes.Text('=')
+            node += nodes.inline('', param.default, classes=['default_value'])
+
+        params += node
+
+    return params
+
+
 def _pseudo_parse_arglist(signode: desc_signature, arglist: str) -> None:
     """"Parse" a list of arguments separated by commas.
 
@@ -284,7 +313,15 @@ def handle_signature(self, sig: str, signode: desc_signature) -> Tuple[str, str]
 
         signode += addnodes.desc_name(name, name)
         if arglist:
-            _pseudo_parse_arglist(signode, arglist)
+            try:
+                signode += _parse_arglist(arglist)
+            except SyntaxError:
+                # fallback to parse arglist original parser.
+                # it supports to represent optional arguments (ex. "func(foo [, bar])")
+                _pseudo_parse_arglist(signode, arglist)
+            except NotImplementedError as exc:
+                logger.warning(exc)
+                _pseudo_parse_arglist(signode, arglist)
         else:
             if self.needs_arglist():
                 # for callables, add an empty parameter list
diff --git a/tests/test_build_html.py b/tests/test_build_html.py
index 63a5948af6f..ef1a36fc853 100644
--- a/tests/test_build_html.py
+++ b/tests/test_build_html.py
@@ -177,7 +177,7 @@ def test_html4_output(app, status, warning):
     ],
     'autodoc.html': [
         (".//dt[@id='autodoc_target.Class']", ''),
-        (".//dt[@id='autodoc_target.function']/em", r'\*\*kwds'),
+        (".//dt[@id='autodoc_target.function']/em/span[@class='argument']", r'\*\*kwds'),
         (".//dd/p", r'Return spam\.'),
     ],
     'extapi.html': [
diff --git a/tests/test_domain_py.py b/tests/test_domain_py.py
index 3ff29cbb7a6..e67719a130d 100644
--- a/tests/test_domain_py.py
+++ b/tests/test_domain_py.py
@@ -223,7 +223,43 @@ def test_pyfunction_signature(app):
                                   desc_content)]))
     assert_node(doctree[1], addnodes.desc, desctype="function",
                 domain="py", objtype="function", noindex=False)
-    assert_node(doctree[1][0][1], [desc_parameterlist, desc_parameter, "name: str"])
+    assert_node(doctree[1][0][1],
+                [desc_parameterlist, desc_parameter, ([nodes.inline, "name"],
+                                                      ": ",
+                                                      [nodes.inline, "str"])])
+
+
+def test_pyfunction_signature_full(app):
+    text = (".. py:function:: hello(a: str, b = 1, *args: str, "
+            "c: bool = True, **kwargs: str) -> str")
+    doctree = restructuredtext.parse(app, text)
+    assert_node(doctree, (addnodes.index,
+                          [desc, ([desc_signature, ([desc_name, "hello"],
+                                                    desc_parameterlist,
+                                                    [desc_returns, "str"])],
+                                  desc_content)]))
+    assert_node(doctree[1], addnodes.desc, desctype="function",
+                domain="py", objtype="function", noindex=False)
+    assert_node(doctree[1][0][1],
+                [desc_parameterlist, ([desc_parameter, ([nodes.inline, "a"],
+                                                        ": ",
+                                                        [nodes.inline, "str"])],
+                                      [desc_parameter, ([nodes.inline, "b"],
+                                                        "=",
+                                                        [nodes.inline, "1"])],
+                                      [desc_parameter, ([nodes.inline, "*args"],
+                                                        ": ",
+                                                        [nodes.inline, "str"])],
+                                      [desc_parameter, ([nodes.inline, "c"],
+                                                        ": ",
+                                                        [nodes.inline, "bool"],
+                                                        " = ",
+                                                        [nodes.inline, "True"])],
+                                      [desc_parameter, ([nodes.inline, "**kwargs"],
+                                                        ": ",
+                                                        [nodes.inline, "str"])])])
+
+
 
 
 def test_optional_pyfunction_signature(app):