diff --git a/sources/src/citygml/citymodel.cpp b/sources/src/citygml/citymodel.cpp
index e6c0d60c..b1887fc1 100644
--- a/sources/src/citygml/citymodel.cpp
+++ b/sources/src/citygml/citymodel.cpp
@@ -55,7 +55,7 @@ namespace citygml
             it->second.push_back(cityObj);
         }
 
-        for (int i = 0; i < cityObj->getChildCityObjectsCount(); i++) {
+        for (unsigned int i = 0; i < cityObj->getChildCityObjectsCount(); i++) {
             addToCityObjectsMapRecursive(&cityObj->getChildCityObject(i));
         }
     }
diff --git a/sources/src/citygml/cityobject.cpp b/sources/src/citygml/cityobject.cpp
index 6c968ea1..7266fea0 100644
--- a/sources/src/citygml/cityobject.cpp
+++ b/sources/src/citygml/cityobject.cpp
@@ -125,7 +125,7 @@ namespace citygml {
         }
 
         for (std::unique_ptr<ImplicitGeometry>& implictGeom : m_implicitGeometries) {
-            for (int i = 0; i < implictGeom->getGeometriesCount(); i++) {
+            for (unsigned int i = 0; i < implictGeom->getGeometriesCount(); i++) {
                 implictGeom->getGeometry(i).finish(tesselator, optimize, logger);
             }
         }
diff --git a/sources/src/parser/geometryelementparser.cpp b/sources/src/parser/geometryelementparser.cpp
index c608c202..c641d8e4 100644
--- a/sources/src/parser/geometryelementparser.cpp
+++ b/sources/src/parser/geometryelementparser.cpp
@@ -89,7 +89,7 @@ namespace citygml {
     bool GeometryElementParser::parseElementEndTag(const NodeType::XMLNode&, const std::string&)
     {
         if (m_orientation == "-") {
-            for (int i = 0; i < m_model->getPolygonsCount(); i++) {
+            for (unsigned int i = 0; i < m_model->getPolygonsCount(); i++) {
                 m_model->getPolygon(i)->setNegNormal(true);
             }
         }