diff --git a/A00_Common/spreadsheet/spreadsheet_grid.ts b/A00_Common/spreadsheet/spreadsheet_grid.ts
index 9e0b97db7..416f5dd62 100644
--- a/A00_Common/spreadsheet/spreadsheet_grid.ts
+++ b/A00_Common/spreadsheet/spreadsheet_grid.ts
@@ -437,6 +437,16 @@ export function createGrid(ctx: SpreadsheetContext): GridHandle {
     };
   }
 
+  /** 굴리는 영역 밖 테두리 자르기(`overlay` 좌표) — 고정 머리 칸 · 모서리 · 스크롤바 위로 안 나가게(요구 566). */
+  function clipOf(b: CellBox, inFrozenCol: boolean, inFrozenRow: boolean): string {
+    const pad = (n: number): number => Math.max(0, Math.ceil(n));
+    const top = inFrozenRow ? 0 : pad(frozenH - b.y);
+    const left = inFrozenCol ? 0 : pad(frozenW - b.x);
+    const bottom = pad(b.y + b.h - (frozenH + paneBR.clientHeight));
+    const right = pad(b.x + b.w - (frozenW + paneBR.clientWidth));
+    return `inset(${top}px ${right}px ${bottom}px ${left}px)`;
+  }
+
   function renderSelection(): void {
     let selLayer = overlay.querySelector<HTMLElement>(".aislo-grid__sel-layer");
     if (!selLayer) {
@@ -470,6 +480,7 @@ export function createGrid(ctx: SpreadsheetContext): GridHandle {
       node.style.height = `${screen.h}px`;
       node.style.borderColor = "var(--aislo-grid-selected)";
       node.style.borderWidth = i === 0 ? "2px" : "1px";
+      node.style.clipPath = clipOf(screen, inFrozenCol, inFrozenRow);
       selLayer!.append(node);
     }
     // 활성 칸 테두리 — 칸 다시 그리기(`renderRowOfCells`) 없이 고름만 바뀌어도 옛 칸에 남지 않게.
@@ -487,6 +498,17 @@ export function createGrid(ctx: SpreadsheetContext): GridHandle {
     handle.className = "aislo-grid__fill-handle";
     handle.style.left = `${corner.x + corner.w - 4}px`;
     handle.style.top = `${corner.y + corner.h - 4}px`;
+    const hx = corner.x + corner.w;
+    const hy = corner.y + corner.h;
+    const hFC = handleAt.c < frozenCols;
+    const hFR = handleAt.r < frozenRows;
+    if (
+      (!hFC && hx < frozenW) ||
+      (!hFR && hy < frozenH) ||
+      hx > frozenW + paneBR.clientWidth ||
+      hy > frozenH + paneBR.clientHeight
+    )
+      handle.style.display = "none";
     selLayer!.append(handle);
   }
 
@@ -525,6 +547,16 @@ export function createGrid(ctx: SpreadsheetContext): GridHandle {
       node.style.width = `${merged.w}px`;
       node.style.height = `${merged.h}px`;
       node.style.borderColor = REF_COLORS[ref.색번호 % REF_COLORS.length];
+      node.style.clipPath = clipOf(
+        {
+          x: parseFloat(node.style.left),
+          y: parseFloat(node.style.top),
+          w: merged.w,
+          h: merged.h,
+        },
+        inFrozenCol,
+        inFrozenRow,
+      );
       refLayer!.append(node);
     }
   }
diff --git a/resources/tester/test_730_grid_sel_clip.py b/resources/tester/test_730_grid_sel_clip.py
new file mode 100644
index 000000000..3f774ec45
--- /dev/null
+++ b/resources/tester/test_730_grid_sel_clip.py
@@ -0,0 +1,30 @@
+"""730-1 지킴 — 엑셀 격자 고른 범위 · 참조 테두리 · 채우기 손잡이는 굴리는 영역 밖으로 안 나감(요구 566).
+화면 수치 판정은 tmp 의 playwright 일회 검증 · 여기서는 자르기 길이 빠지지 않았는지만 지킴."""
+
+import re
+from pathlib import Path
+
+SRC = (Path(__file__).parents[2] / "A00_Common/spreadsheet/spreadsheet_grid.ts").read_text(
+    encoding="utf-8"
+)
+
+
+def body(name: str) -> str:
+    m = re.search(rf"function {name}\(.*?\n  }}\n", SRC, re.S)
+    assert m, name
+    return m.group(0)
+
+
+def test_clip_helper_uses_frozen_and_pane_size():
+    h = body("clipOf")
+    assert "frozenH" in h and "frozenW" in h
+    assert "paneBR.clientHeight" in h and "paneBR.clientWidth" in h
+
+
+def test_selection_and_ref_borders_are_clipped():
+    assert "clipPath = clipOf(" in body("renderSelection")
+    assert "clipPath = clipOf(" in body("setRefHighlights")
+
+
+def test_fill_handle_hidden_outside_view():
+    assert 'handle.style.display = "none"' in body("renderSelection")