diff --git a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/QueryMapper.java b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/QueryMapper.java
index 2ba9b8862..6f10a9a6f 100644
--- a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/QueryMapper.java
+++ b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/QueryMapper.java
@@ -200,13 +200,28 @@ public class QueryMapper {
 			return getMappedKeyword(new Keyword((DBObject) value), null);
 		}
 
-		if (documentField.isAssociation()) {
+		if (isAssociationConversionNecessary(documentField, value)) {
 			return convertAssociation(value, documentField.getProperty());
 		}
 
 		return convertSimpleOrDBObject(value, documentField.getPropertyEntity());
 	}
 
+	/**
+	 * Returns whether the given {@link Field} represents an association reference that together with the given value
+	 * requires conversion to a {@link org.springframework.data.mongodb.core.mapping.DBRef} object. We check whether the
+	 * type of the given value is compatible with the type of the given document field in order to deal with potential
+	 * query field exclusions, since MongoDB uses the {@code int} {@literal 0} as an indicator for an excluded field.
+	 * 
+	 * @param documentField
+	 * @param value
+	 * @return
+	 */
+	private boolean isAssociationConversionNecessary(Field documentField, Object value) {
+		return documentField.isAssociation() && value != null
+				&& documentField.getProperty().getActualType().isAssignableFrom(value.getClass());
+	}
+
 	/**
 	 * Retriggers mapping if the given source is a {@link DBObject} or simply invokes the
 	 * 
@@ -248,7 +263,8 @@ public class QueryMapper {
 	 */
 	private Object convertAssociation(Object source, MongoPersistentProperty property) {
 
-		if (property == null || !property.isAssociation()) {
+		if (property == null || !property.isAssociation() || source == null || source instanceof DBRef
+				|| !property.isEntity()) {
 			return source;
 		}
 
@@ -270,7 +286,7 @@ public class QueryMapper {
 			return result;
 		}
 
-		return source == null || source instanceof DBRef ? source : converter.toDBRef(source, property);
+		return converter.toDBRef(source, property);
 	}
 
 	/**
diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/QueryMapperUnitTests.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/QueryMapperUnitTests.java
index 34cd8716d..3b69748c9 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/QueryMapperUnitTests.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/QueryMapperUnitTests.java
@@ -56,6 +56,7 @@ import com.mongodb.QueryBuilder;
  * 
  * @author Oliver Gierke
  * @author Patryk Wasik
+ * @author Thomas Darimont
  */
 @RunWith(MockitoJUnitRunner.class)
 public class QueryMapperUnitTests {
@@ -466,6 +467,23 @@ public class QueryMapperUnitTests {
 		assertThat(result.get("myvalue"), is((Object) "$center"));
 	}
 
+	/**
+	 * @DATAMONGO-805
+	 */
+	@Test
+	public void shouldExcludeDBRefAssociation() {
+
+		Query query = query(where("someString").is("foo"));
+		query.fields().exclude("reference");
+
+		BasicMongoPersistentEntity<?> entity = context.getPersistentEntity(WithDBRef.class);
+		DBObject queryResult = mapper.getMappedObject(query.getQueryObject(), entity);
+		DBObject fieldsResult = mapper.getMappedObject(query.getFieldsObject(), entity);
+
+		assertThat(queryResult.get("someString"), is((Object) "foo"));
+		assertThat(fieldsResult.get("reference"), is((Object) 0));
+	}
+
 	class IdWrapper {
 		Object id;
 	}
diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/mapping/MappingTests.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/mapping/MappingTests.java
index bfd453517..b101ae6ba 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/mapping/MappingTests.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/mapping/MappingTests.java
@@ -24,6 +24,7 @@ import static org.springframework.data.mongodb.core.query.Update.*;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 
@@ -49,6 +50,7 @@ import com.mongodb.MongoException;
 /**
  * @author Jon Brisbin
  * @author Oliver Gierke
+ * @author Thomas Darimont
  */
 public class MappingTests extends AbstractIntegrationTests {
 
@@ -465,6 +467,57 @@ public class MappingTests extends AbstractIntegrationTests {
 		assertThat(result.items.get(0).id, is(items.id));
 	}
 
+	/**
+	 * @see DATAMONGO-805
+	 */
+	@Test
+	public void supportExcludeDbRefAssociation() {
+
+		template.dropCollection(Item.class);
+		template.dropCollection(Container.class);
+
+		Item item = new Item();
+		template.insert(item);
+
+		Container container = new Container("foo");
+		container.item = item;
+
+		template.insert(container);
+
+		Query query = new Query(Criteria.where("id").is("foo"));
+		query.fields().exclude("item");
+		Container result = template.findOne(query, Container.class);
+
+		assertThat(result, is(notNullValue()));
+		assertThat(result.item, is(nullValue()));
+	}
+
+	/**
+	 * @see DATAMONGO-805
+	 */
+	@Test
+	public void shouldMapFieldsOfIterableEntity() {
+
+		template.dropCollection(IterableItem.class);
+		template.dropCollection(Container.class);
+
+		Item item = new IterableItem();
+		item.value = "bar";
+		template.insert(item);
+
+		Container container = new Container("foo");
+		container.item = item;
+
+		template.insert(container);
+
+		Query query = new Query(Criteria.where("id").is("foo"));
+		Container result = template.findOne(query, Container.class);
+
+		assertThat(result, is(notNullValue()));
+		assertThat(result.item, is(notNullValue()));
+		assertThat(result.item.value, is("bar"));
+	}
+
 	static class Container {
 
 		@Id final String id;
@@ -473,6 +526,10 @@ public class MappingTests extends AbstractIntegrationTests {
 			id = new ObjectId().toString();
 		}
 
+		public Container(String id) {
+			this.id = id;
+		}
+
 		@DBRef Item item;
 		@DBRef List<Item> items;
 	}
@@ -480,9 +537,26 @@ public class MappingTests extends AbstractIntegrationTests {
 	static class Item {
 
 		@Id final String id;
+		String value;
 
 		public Item() {
 			this.id = new ObjectId().toString();
 		}
 	}
+
+	static class IterableItem extends Item implements Iterable<ItemData> {
+
+		List<ItemData> data = new ArrayList<MappingTests.ItemData>();
+
+		@Override
+		public Iterator<ItemData> iterator() {
+			return data.iterator();
+		}
+	}
+
+	static class ItemData {
+
+		String id;
+		String value;
+	}
 }