diff --git a/src/admesh/stlinit.cpp b/src/admesh/stlinit.cpp
index f1be4ac77c..095f7f715a 100644
--- a/src/admesh/stlinit.cpp
+++ b/src/admesh/stlinit.cpp
@@ -237,7 +237,17 @@ static bool stl_read(stl_file *stl, FILE *fp, int first_facet, bool first, Impor
 		}
 #endif
 
-		// Write the facet into memory.
+		// Write the facet into memory if none of facet vertices is NAN.
+		bool someone_is_nan = false;
+		for (size_t j = 0; j < 3; ++j) {
+			if (isnan(facet.vertex[j](0)) || isnan(facet.vertex[j](1)) || isnan(facet.vertex[j](2))) { 
+				someone_is_nan = true;
+				break; 
+			}
+		}
+		if(someone_is_nan)
+            continue;
+
 		stl->facet_start[i] = facet;
 		stl_facet_stats(stl, facet, first);
   	}