diff --git a/library/think/Model.php b/library/think/Model.php
index e617b646..5d112e44 100644
--- a/library/think/Model.php
+++ b/library/think/Model.php
@@ -192,7 +192,7 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
         $con = Db::connect($connection);
         // 设置当前模型 确保查询返回模型对象
         $queryClass = $this->query ?: $con->getConfig('query');
-        $query      = new $queryClass($con, $this->class);
+        $query      = new $queryClass($con, $this);
 
         // 设置当前数据表和模型名
         if (!empty($this->table)) {
@@ -208,6 +208,19 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
         return $query;
     }
 
+    /**
+     * 创建新的模型实例
+     * @access public
+     * @param  array|object $data 数据
+     * @param  bool         $isUpdate 是否为更新
+     * @param  mixed        $where 更新条件
+     * @return Model
+     */
+    public function newInstance($data = [], $isUpdate = false, $where = null)
+    {
+        return (new static($data))->isUpdate($isUpdate, $where);
+    }
+
     /**
      * 获取当前模型的查询对象
      * @access public
@@ -599,7 +612,7 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
      */
     protected function getRelationData(Relation $modelRelation)
     {
-        if ($this->parent && get_class($this->parent) == $modelRelation->getModel()) {
+        if ($this->parent && $modelRelation->getModel() == $this->parent) {
             $value = $this->parent;
         } else {
             // 首先获取关联数据
diff --git a/library/think/db/Query.php b/library/think/db/Query.php
index b3d365a7..8ee6e15c 100644
--- a/library/think/db/Query.php
+++ b/library/think/db/Query.php
@@ -58,9 +58,9 @@ class Query
      * 构造函数
      * @access public
      * @param Connection $connection 数据库对象实例
-     * @param string     $model      模型名
+     * @param Model      $model      模型对象
      */
-    public function __construct(Connection $connection = null, $model = '')
+    public function __construct(Connection $connection = null, $model = null)
     {
         $this->connection = $connection ?: Db::connect([], true);
         $this->prefix     = $this->connection->getConfig('prefix');
@@ -133,7 +133,7 @@ class Query
     /**
      * 获取当前的模型对象名
      * @access public
-     * @return string
+     * @return Model|null
      */
     public function getModel()
     {
@@ -1910,11 +1910,10 @@ class Query
             $with = explode(',', $with);
         }
 
-        $first        = true;
-        $currentModel = $this->model;
+        $first = true;
 
         /** @var Model $class */
-        $class = new $currentModel;
+        $class = $this->model;
         foreach ($with as $key => $relation) {
             $subRelation = '';
             $closure     = false;
@@ -1973,7 +1972,7 @@ class Query
                     $relation = $key;
                 }
                 $relation = Loader::parseName($relation, 1, false);
-                $count    = '(' . (new $this->model)->$relation()->getRelationCountQuery($closure) . ')';
+                $count    = '(' . $this->model->$relation()->getRelationCountQuery($closure) . ')';
                 $this->field([$count => Loader::parseName($relation) . '_count']);
             }
         }
@@ -2365,11 +2364,10 @@ class Query
         // 数据列表读取后的处理
         if (!empty($this->model)) {
             // 生成模型对象
-            $modelName = $this->model;
             if (count($resultSet) > 0) {
                 foreach ($resultSet as $key => $result) {
                     /** @var Model $model */
-                    $model = new $modelName($result);
+                    $model = $this->model->newInstance($result);
                     $model->isUpdate(true);
 
                     // 关联查询
@@ -2389,7 +2387,7 @@ class Query
                 // 模型数据集转换
                 $resultSet = $model->toCollection($resultSet);
             } else {
-                $resultSet = (new $modelName)->toCollection($resultSet);
+                $resultSet = $this->model->toCollection($resultSet);
             }
         } elseif ('collection' == $this->connection->getConfig('resultset_type')) {
             // 返回Collection对象
@@ -2525,8 +2523,7 @@ class Query
         if (!empty($result)) {
             if (!empty($this->model)) {
                 // 返回模型对象
-                $model  = $this->model;
-                $result = new $model($result);
+                $result = $this->model->newInstance($result);
                 $result->isUpdate(true, isset($options['where']['AND']) ? $options['where']['AND'] : null);
                 // 关联查询
                 if (!empty($options['relation'])) {
@@ -2557,7 +2554,8 @@ class Query
     protected function throwNotFound($options = [])
     {
         if (!empty($this->model)) {
-            throw new ModelNotFoundException('model data Not Found:' . $this->model, $this->model, $options);
+            $class = get_class($this->model);
+            throw new ModelNotFoundException('model data Not Found:' . $class, $class, $options);
         } else {
             $table = is_array($options['table']) ? key($options['table']) : $options['table'];
             throw new DataNotFoundException('table data not Found:' . $table, $table, $options);
diff --git a/library/think/model/Relation.php b/library/think/model/Relation.php
index 21cbdfd8..f4c5781e 100644
--- a/library/think/model/Relation.php
+++ b/library/think/model/Relation.php
@@ -49,11 +49,11 @@ abstract class Relation
     /**
      * 获取当前的关联模型类
      * @access public
-     * @return string
+     * @return Model
      */
     public function getModel()
     {
-        return $this->model;
+        return $this->query->getModel();
     }
 
     /**
diff --git a/library/think/model/relation/OneToOne.php b/library/think/model/relation/OneToOne.php
index 647fa8e9..02d7d563 100644
--- a/library/think/model/relation/OneToOne.php
+++ b/library/think/model/relation/OneToOne.php
@@ -57,18 +57,18 @@ abstract class OneToOne extends Relation
      */
     public function eagerly(Query $query, $relation, $subRelation, $closure, $first)
     {
-        $name  = Loader::parseName(basename(str_replace('\\', '/', $query->getModel())));
-        $alias = $name;
+        $name = Loader::parseName(basename(str_replace('\\', '/', get_class($query->getModel()))));
+
         if ($first) {
             $table = $query->getTable();
-            $query->table([$table => $alias]);
+            $query->table([$table => $name]);
             if ($query->getOptions('field')) {
                 $field = $query->getOptions('field');
                 $query->removeOption('field');
             } else {
                 $field = true;
             }
-            $query->field($field, false, $table, $alias);
+            $query->field($field, false, $table, $name);
             $field = null;
         }
 
@@ -78,9 +78,9 @@ abstract class OneToOne extends Relation
         $query->via($joinAlias);
 
         if ($this instanceof BelongsTo) {
-            $query->join([$joinTable => $joinAlias], $alias . '.' . $this->foreignKey . '=' . $joinAlias . '.' . $this->localKey, $this->joinType);
+            $query->join([$joinTable => $joinAlias], $name . '.' . $this->foreignKey . '=' . $joinAlias . '.' . $this->localKey, $this->joinType);
         } else {
-            $query->join([$joinTable => $joinAlias], $alias . '.' . $this->localKey . '=' . $joinAlias . '.' . $this->foreignKey, $this->joinType);
+            $query->join([$joinTable => $joinAlias], $name . '.' . $this->localKey . '=' . $joinAlias . '.' . $this->foreignKey, $this->joinType);
         }
 
         if ($closure) {