diff --git a/docs/changelog.rst b/docs/changelog.rst
index dfbffa0..beb05f5 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -15,6 +15,7 @@ Changelog
    applied. Uninstalling from the same panel removes the PAS plugin
    and the per-user JWT signing secrets.
 
+- #91 Add DataGridFieldManager to fix UID reference validation in DataGrid fields
 - #90 Fix JWT authentication security issues
 - #88 Add Bearer token (JWT) authentication via PAS plugin
 - #89 Fix inherited schema fields missing for multi-schema Dexterity types
diff --git a/src/senaite/jsonapi/configure.zcml b/src/senaite/jsonapi/configure.zcml
index aaeea08..1442fae 100644
--- a/src/senaite/jsonapi/configure.zcml
+++ b/src/senaite/jsonapi/configure.zcml
@@ -204,6 +204,11 @@
       factory=".fieldmanagers.DXUIDReferenceFieldManager"
       />
 
+  <!-- Adapter for DX DataGridField Field -->
+  <adapter
+      for="senaite.core.schema.interfaces.IDataGridField"
+      factory=".fieldmanagers.DataGridFieldManager"
+      />
 
   <!-- ZOPE SCHEMA FIELD MANAGERS
        Field level interface to get and set values and get a JSON compatible
diff --git a/src/senaite/jsonapi/fieldmanagers.py b/src/senaite/jsonapi/fieldmanagers.py
index cca9606..60223e1 100644
--- a/src/senaite/jsonapi/fieldmanagers.py
+++ b/src/senaite/jsonapi/fieldmanagers.py
@@ -24,12 +24,14 @@
 from AccessControl import Unauthorized
 from DateTime import DateTime
 from Products.Archetypes.utils import mapply
+from senaite.core.schema.uidreferencefield import UIDReferenceField
 from senaite.jsonapi import api
 from senaite.jsonapi import logger
 from senaite.jsonapi import underscore as u
 from senaite.jsonapi.interfaces import IFieldManager
 from zope import interface
 from zope.interface import implementer
+from zope.schema import getFields
 from zope.schema._bootstrapinterfaces import WrongContainedType
 from zope.schema._bootstrapinterfaces import WrongType
 
@@ -94,6 +96,35 @@ def _get(self, instance, **kw):
         return self.field.get(instance)
 
 
+class DataGridFieldManager(ZopeSchemaFieldManager):
+    """Adapter to get/set the value of DataGridField (grid/records) fields
+    """
+    interface.implements(IFieldManager)
+
+    def _normalize_datagrid(self, value):
+        schema = self.field.value_type.schema
+
+        for row in value:
+            for name, field in getFields(schema).items():
+                if isinstance(field, UIDReferenceField):
+                    uid = row.get(name)
+                    if not uid:
+                        continue
+                    # UIDReferenceField sub-fields nested inside a DataGridRow
+                    # always require a list of native `str` UIDs
+                    if isinstance(uid, list):
+                        row[name] = [str(u) for u in uid]
+                    else:
+                        row[name] = [str(uid)]
+        return value
+
+    def set(self, instance, value, **kw):
+        """Set the value of the field
+        """
+        value = self._normalize_datagrid(value)
+        return self._set(instance, value, **kw)
+
+
 class DatetimeFieldManager(ZopeSchemaFieldManager):
     """Adapter to get/set the value of Datetime Fields
     """