diff --git a/src/ol/control/ScaleLine.js b/src/ol/control/ScaleLine.js
index b4f91201b7..338821bcea 100644
--- a/src/ol/control/ScaleLine.js
+++ b/src/ol/control/ScaleLine.js
@@ -289,7 +289,7 @@ class ScaleLine extends Control {
       }
     } else if (units == Units.NAUTICAL) {
       pointResolution /= 1852;
-      suffix = 'nm';
+      suffix = 'NM';
     } else if (units == Units.METRIC) {
       if (nominalCount < 0.001) {
         suffix = 'μm';
diff --git a/test/browser/spec/ol/control/scaleline.test.js b/test/browser/spec/ol/control/scaleline.test.js
index 85cdefc536..ee059b3f63 100644
--- a/test/browser/spec/ol/control/scaleline.test.js
+++ b/test/browser/spec/ol/control/scaleline.test.js
@@ -221,7 +221,7 @@ describe('ol.control.ScaleLine', function () {
 
       ctrl.setUnits('nautical');
       map.renderSync();
-      expect(ctrl.element.innerText).to.be('10000 nm');
+      expect(ctrl.element.innerText).to.be('10000 NM');
     });
   });
 
@@ -411,7 +411,7 @@ describe('ol.control.ScaleLine', function () {
       expect(ctrl.element.innerText).to.be('500 ft');
 
       ctrl.setUnits('nautical');
-      expect(ctrl.element.innerText).to.be('0.05 nm');
+      expect(ctrl.element.innerText).to.be('0.05 NM');
 
       ctrl.setUnits('us');
       expect(ctrl.element.innerText).to.be('500 ft');
@@ -440,7 +440,7 @@ describe('ol.control.ScaleLine', function () {
       expect(ctrl.element.innerText).to.be('5 in');
 
       ctrl.setUnits('nautical');
-      expect(ctrl.element.innerText).to.be('0.00005 nm');
+      expect(ctrl.element.innerText).to.be('0.00005 NM');
 
       ctrl.setUnits('us');
       expect(ctrl.element.innerText).to.be('5 in');