diff --git a/library/think/model/relation/BelongsTo.php b/library/think/model/relation/BelongsTo.php
index 9b66e0c3..45118fc9 100644
--- a/library/think/model/relation/BelongsTo.php
+++ b/library/think/model/relation/BelongsTo.php
@@ -97,6 +97,7 @@ class BelongsTo extends OneToOne
         }
         return $this->parent->db()->alias($model)
             ->field($model . '.*')
+            ->group($model . '.' . $this->foreignKey)
             ->join($table . ' ' . $relation, $model . '.' . $this->foreignKey . '=' . $relation . '.' . $this->localKey, $this->joinType)
             ->where($where);
     }
diff --git a/library/think/model/relation/HasMany.php b/library/think/model/relation/HasMany.php
index eb9bf66d..ccc210e3 100644
--- a/library/think/model/relation/HasMany.php
+++ b/library/think/model/relation/HasMany.php
@@ -271,6 +271,7 @@ class HasMany extends Relation
         }
         return $this->parent->db()->alias($model)
             ->field($model . '.*')
+            ->group($model . '.' . $this->localKey)
             ->join($table . ' ' . $relation, $model . '.' . $this->localKey . '=' . $relation . '.' . $this->foreignKey)
             ->where($where);
     }