diff --git a/src/geo/Extent.js b/src/geo/Extent.js
index 031f3943a..1c0a97274 100644
--- a/src/geo/Extent.js
+++ b/src/geo/Extent.js
@@ -547,7 +547,7 @@ class Extent {
             //FIXME a rare but potential bug:
             //An extent may be projected by multiple projection
             if (ext._dirty) {
-                let minmax = [ext.getMin(), ext.getMax()];
+                let minmax = [new Coordinate(ext.xmax, ext.ymin), new Coordinate(ext.xmin, ext.ymax)];
                 minmax = proj.projectCoords(minmax);
                 const min = minmax[0],
                     max = minmax[1];
diff --git a/test/geometry/ExtentSpec.js b/test/geometry/ExtentSpec.js
index 49c5a5c5e..af151b8ac 100644
--- a/test/geometry/ExtentSpec.js
+++ b/test/geometry/ExtentSpec.js
@@ -197,6 +197,12 @@ describe('ExtentSpec', function () {
             expect(ext1.contains(new maptalks.Point(20, 20))).to.not.be.ok();
         });
 
+        //#899
+        it('contains with projection', function () {
+            var ext = new maptalks.Extent([-170, -80, 170, 80], maptalks.projection.EPSG3857);
+
+            expect(ext.contains(new maptalks.Coordinate([-0.113049,51.49856]))).to.be.ok();
+        });
     });