diff --git a/src/Functions/FunctionsConversion.cpp b/src/Functions/FunctionsConversion.cpp
index 0f6311c9716..5f1583f6e71 100644
--- a/src/Functions/FunctionsConversion.cpp
+++ b/src/Functions/FunctionsConversion.cpp
@@ -4390,7 +4390,7 @@ private:
                     variant_column = IColumn::mutate(column);
                 /// Otherwise we should filter column.
                 else
-                    variant_column = column->filter(filter, variant_size_hint)->assumeMutable();
+                    variant_column = IColumn::mutate(column->filter(filter, variant_size_hint));
 
                 assert_cast<ColumnLowCardinality &>(*variant_column).nestedRemoveNullable();
                 return createVariantFromDescriptorsAndOneNonEmptyVariant(variant_types, std::move(discriminators), std::move(variant_column), variant_discr);
diff --git a/tests/queries/0_stateless/03261_low_cardinality_nullable_to_dynamic_cast.reference b/tests/queries/0_stateless/03261_low_cardinality_nullable_to_dynamic_cast.reference
new file mode 100644
index 00000000000..96e34d5a44c
--- /dev/null
+++ b/tests/queries/0_stateless/03261_low_cardinality_nullable_to_dynamic_cast.reference
@@ -0,0 +1,2 @@
+\N
+\N
diff --git a/tests/queries/0_stateless/03261_low_cardinality_nullable_to_dynamic_cast.sql b/tests/queries/0_stateless/03261_low_cardinality_nullable_to_dynamic_cast.sql
new file mode 100644
index 00000000000..fdb497a62bf
--- /dev/null
+++ b/tests/queries/0_stateless/03261_low_cardinality_nullable_to_dynamic_cast.sql
@@ -0,0 +1,7 @@
+SET allow_suspicious_low_cardinality_types = 1, allow_experimental_dynamic_type = 1;
+DROP TABLE IF EXISTS t0;
+CREATE TABLE t0 (c0 LowCardinality(Nullable(Int))) ENGINE = Memory();
+INSERT INTO TABLE t0 (c0) VALUES (NULL);
+SELECT c0::Dynamic FROM t0;
+SELECT c0 FROM t0;
+DROP TABLE t0;