diff --git a/embedded_ansi_test.go b/embedded_ansi_test.go
new file mode 100644
index 00000000..2e75bdfc
--- /dev/null
+++ b/embedded_ansi_test.go
@@ -0,0 +1,34 @@
+package lipgloss
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/charmbracelet/x/ansi"
+)
+
+// TestSpaceStylerPreservesEmbeddedANSI verifies that when a space styler is
+// active (underline or strikethrough), Render does not mangle ANSI escape
+// sequences already present in the input, such as a previously-rendered string.
+// See https://github.com/charmbracelet/lipgloss/issues/233.
+func TestSpaceStylerPreservesEmbeddedANSI(t *testing.T) {
+	for _, tc := range []struct {
+		name  string
+		style Style
+	}{
+		{"strikethrough", NewStyle().Strikethrough(true)},
+		{"underline", NewStyle().Underline(true)},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			inner := NewStyle().Bold(true).Render("hi") // "\x1b[1mhi\x1b[m"
+			got := tc.style.Render(inner)
+
+			if w := ansi.StringWidth(got); w != 2 {
+				t.Errorf("visible width = %d, want 2 (embedded ANSI leaked as text): %q", w, got)
+			}
+			if !strings.Contains(got, "\x1b[1m") {
+				t.Errorf("embedded bold sequence was mangled, not preserved verbatim: %q", got)
+			}
+		})
+	}
+}
diff --git a/style.go b/style.go
index 3cd65952..0c646eea 100644
--- a/style.go
+++ b/style.go
@@ -426,13 +426,28 @@ func (s Style) Render(strs ...string) string {
 				b.WriteRune('\n')
 			}
 			if useSpaceStyler {
-				// Look for spaces and apply a different styler
-				for _, r := range line {
-					if unicode.IsSpace(r) {
-						b.WriteString(teSpace.Styled(string(r)))
-						continue
+				// Look for spaces and apply a different styler, while passing
+				// through any ANSI escape sequences already present in the line
+				// so they are not mangled (e.g. when rendering an
+				// already-styled string).
+				// See https://github.com/charmbracelet/lipgloss/issues/233.
+				var state byte
+				for len(line) > 0 {
+					seq, width, n, newState := ansi.DecodeSequence(line, state, nil)
+					if n == 0 {
+						break
 					}
-					b.WriteString(te.Styled(string(r)))
+					switch {
+					case width == 0:
+						// Control or escape sequence: emit verbatim, unstyled.
+						b.WriteString(seq)
+					case isSpaceSequence(seq):
+						b.WriteString(teSpace.Styled(seq))
+					default:
+						b.WriteString(te.Styled(seq))
+					}
+					line = line[n:]
+					state = newState
 				}
 			} else {
 				b.WriteString(te.Styled(line))
@@ -525,6 +540,17 @@ func (s Style) Render(strs ...string) string {
 	return str
 }
 
+// isSpaceSequence reports whether the given grapheme consists solely of
+// whitespace runes.
+func isSpaceSequence(s string) bool {
+	for _, r := range s {
+		if !unicode.IsSpace(r) {
+			return false
+		}
+	}
+	return s != ""
+}
+
 func (s Style) maybeConvertTabs(str string) string {
 	tw := tabWidthDefault
 	if s.isSet(tabWidthKey) {