diff --git a/B04_wf1_Surface/B04_wf1_Surface_UI_MapViewer.ts b/B04_wf1_Surface/B04_wf1_Surface_UI_MapViewer.ts
index 1b1aab8a..a5dac98e 100644
--- a/B04_wf1_Surface/B04_wf1_Surface_UI_MapViewer.ts
+++ b/B04_wf1_Surface/B04_wf1_Surface_UI_MapViewer.ts
@@ -135,8 +135,9 @@ export function createSurfaceMapViewer(): SurfaceMapViewer {
   let meta: VWorldMeta | null = null;
   const geoJsonLayers = new Map<GisLayer, GeoJsonCollection>();
   const activeBackgrounds = new Set<BackgroundLayer>(BACKGROUND_LAYERS);
-  const activeGisLayers = new Set<GisLayer>(GIS_LAYERS);
-  let showContourLabels = false;
+  // gpkg 등고선은 기본 꺼짐(도엽 등고선이 기본 표기), 등고 라벨은 기본 켜짐 (2026-07-26 사용자 지시)
+  const activeGisLayers = new Set<GisLayer>(GIS_LAYERS.filter((layer) => layer !== "등고선"));
+  let showContourLabels = true;
   let scale = 1;
   let offsetX = 0;
   let offsetY = 0;
@@ -151,9 +152,10 @@ export function createSurfaceMapViewer(): SurfaceMapViewer {
   ): HTMLButtonElement {
     const button = document.createElement("button");
     button.type = "button";
-    button.className = "b04-map__layer-button is-active";
+    const initialActive = activeLayers.has(layer);
+    button.className = "b04-map__layer-button" + (initialActive ? " is-active" : "");
     button.textContent = label;
-    button.setAttribute("aria-pressed", "true");
+    button.setAttribute("aria-pressed", String(initialActive));
     if (color) {
       button.classList.add("b04-map__layer-button--gis");
       button.style.setProperty("--b04-layer-color", color);
@@ -196,12 +198,12 @@ export function createSurfaceMapViewer(): SurfaceMapViewer {
     );
   });
 
-  // 등고 라벨 보기/숨기기 (기본 숨김 — 등고선·도엽 등고선의 계곡선 수치 표기)
+  // 등고 라벨 보기/숨기기 (기본 켜짐 — 등고선·도엽 등고선의 계곡선 수치 표기)
   const contourLabelButton = document.createElement("button");
   contourLabelButton.type = "button";
-  contourLabelButton.className = "b04-map__layer-button";
+  contourLabelButton.className = "b04-map__layer-button is-active";
   contourLabelButton.textContent = L("B04_Surface_Map_ContourLabel");
-  contourLabelButton.setAttribute("aria-pressed", "false");
+  contourLabelButton.setAttribute("aria-pressed", "true");
   contourLabelButton.addEventListener("click", () => {
     showContourLabels = !showContourLabels;
     contourLabelButton.classList.toggle("is-active", showContourLabels);