diff --git a/.changeset/ripe-crabs-care.md b/.changeset/ripe-crabs-care.md
new file mode 100644
index 0000000000..d8cdc27652
--- /dev/null
+++ b/.changeset/ripe-crabs-care.md
@@ -0,0 +1,5 @@
+---
+'@backstage/ui': patch
+---
+
+Fixed RadioGroup radio button ellipse distortion by preventing flex shrink and grow.
diff --git a/packages/ui/src/components/RadioGroup/RadioGroup.module.css b/packages/ui/src/components/RadioGroup/RadioGroup.module.css
index acc6d677e4..a18f2d385d 100644
--- a/packages/ui/src/components/RadioGroup/RadioGroup.module.css
+++ b/packages/ui/src/components/RadioGroup/RadioGroup.module.css
@@ -54,6 +54,8 @@
       background: var(--bui-gray-1);
       border-radius: var(--bui-radius-full);
       transition: all 200ms;
+      flex-shrink: 0;
+      flex-grow: 0;
     }
 
     &[data-pressed]:before {