diff --git a/graphify/extract.py b/graphify/extract.py
index 7101d616..19dcaa24 100644
--- a/graphify/extract.py
+++ b/graphify/extract.py
@@ -8495,6 +8495,22 @@ def extract_powershell(path: Path) -> dict:
                 class_nid = _make_id(stem, class_name)
                 add_node(class_nid, class_name, line)
                 add_edge(file_nid, class_nid, "contains", line)
+                # Base type(s) after ':'. PowerShell has no syntactic base vs
+                # interface split, so (matching the C# convention) treat the
+                # first base as the superclass (inherits) and the rest as
+                # interfaces (implements). Bases are the simple_name children
+                # after the ':' token.
+                colon_seen = False
+                base_index = 0
+                for child in node.children:
+                    if child.type == ":":
+                        colon_seen = True
+                    elif colon_seen and child.type == "simple_name":
+                        base_nid = ensure_named_node(_read_text(child, source), line)
+                        if base_nid != class_nid:
+                            rel = "inherits" if base_index == 0 else "implements"
+                            add_edge(class_nid, base_nid, rel, line)
+                        base_index += 1
                 for child in node.children:
                     walk(child, parent_class_nid=class_nid)
             return
diff --git a/tests/fixtures/sample.ps1 b/tests/fixtures/sample.ps1
index 2cdb6aa7..43c27fd7 100644
--- a/tests/fixtures/sample.ps1
+++ b/tests/fixtures/sample.ps1
@@ -30,3 +30,19 @@ class DataProcessor {
         Set-Content -Path $path -Value $this.Source
     }
 }
+
+class Shape {
+    [string]$Kind
+
+    [double] Area() {
+        return 0.0
+    }
+}
+
+class Circle : Shape {
+    [double]$Radius
+
+    [double] Area() {
+        return 3.14159 * $this.Radius * $this.Radius
+    }
+}
diff --git a/tests/test_languages.py b/tests/test_languages.py
index bd370c9d..35569c50 100644
--- a/tests/test_languages.py
+++ b/tests/test_languages.py
@@ -1631,6 +1631,13 @@ def test_powershell_finds_class_and_method():
     assert any("Transform" in l for l in labels)
 
 
+def test_powershell_class_base_type_emits_inherits_edge():
+    # `class Circle : Shape` — the base type after ':' was previously dropped
+    # because the handler only read the first simple_name (the class name).
+    r = extract_powershell(FIXTURES / "sample.ps1")
+    assert ("Circle", "Shape") in _edge_labels(r, "inherits")
+
+
 def test_powershell_property_field_type_context():
     r = extract_powershell(FIXTURES / "sample.ps1")
     assert ("DataProcessor", "string") in _edge_labels(r, "references", "field")