diff --git a/mysql-test/r/binlog.result b/mysql-test/r/binlog.result
index 0a199c87545..e6c5e3222de 100644
--- a/mysql-test/r/binlog.result
+++ b/mysql-test/r/binlog.result
@@ -567,4 +567,19 @@ master-bin.000001	36585	Rotate	1	36629	master-bin.000002;pos=4
 drop table t1;
 set global binlog_cache_size=@bcs;
 set session autocommit = @ac;
+drop table if exists t1;
+reset master;
+create table t1 (a bigint unsigned, b bigint(20) unsigned);
+prepare stmt from "insert into t1 values (?,?)";
+set @a= 9999999999999999;
+set @b= 14632475938453979136;
+execute stmt using @a, @b;
+deallocate prepare stmt;
+drop table t1;
+show binlog events from 0;
+Log_name	Pos	Event_type	Server_id	End_log_pos	Info
+master-bin.000001	4	Format_desc	1	98	Server version, Binlog ver: 4
+master-bin.000001	98	Query	1	219	use `test`; create table t1 (a bigint unsigned, b bigint(20) unsigned)
+master-bin.000001	219	Query	1	343	use `test`; insert into t1 values (9999999999999999,14632475938453979136)
+master-bin.000001	343	Query	1	419	use `test`; drop table t1
 End of 5.0 tests
diff --git a/mysql-test/r/ps.result b/mysql-test/r/ps.result
index f547654bed1..8845f011971 100644
--- a/mysql-test/r/ps.result
+++ b/mysql-test/r/ps.result
@@ -1693,4 +1693,20 @@ t1	CREATE TABLE `t1` (
   `?` decimal(2,1) default NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
+drop table if exists t1;
+create table t1 (a bigint unsigned, b bigint(20) unsigned);
+prepare stmt from "insert into t1 values (?,?)";
+set @a= 9999999999999999;
+set @b= 14632475938453979136;
+insert into t1 values (@a, @b);
+select * from t1 where a = @a and b = @b;
+a	b
+9999999999999999	14632475938453979136
+execute stmt using @a, @b;
+select * from t1 where a = @a and b = @b;
+a	b
+9999999999999999	14632475938453979136
+9999999999999999	14632475938453979136
+deallocate prepare stmt;
+drop table t1;
 End of 5.0 tests.
diff --git a/mysql-test/t/binlog.test b/mysql-test/t/binlog.test
index 5d1399925c3..b35c81b3b18 100644
--- a/mysql-test/t/binlog.test
+++ b/mysql-test/t/binlog.test
@@ -106,4 +106,21 @@ drop table t1;
 set global binlog_cache_size=@bcs;
 set session autocommit = @ac;
 
+#
+# Bug#33798: prepared statements improperly handle large unsigned ints
+#
+--disable_warnings
+drop table if exists t1;
+--enable_warnings
+reset master;
+create table t1 (a bigint unsigned, b bigint(20) unsigned);
+prepare stmt from "insert into t1 values (?,?)";
+set @a= 9999999999999999;
+set @b= 14632475938453979136;
+execute stmt using @a, @b;
+deallocate prepare stmt;
+drop table t1;
+--replace_regex /\/\* xid=.* \*\//\/* XID *\// /table_id: [0-9]+/table_id: #/ /Server ver: [^,]*,/Server version,/
+show binlog events from 0;
+
 --echo End of 5.0 tests
diff --git a/mysql-test/t/ps.test b/mysql-test/t/ps.test
index c1505ffd645..3f4b37f13f4 100644
--- a/mysql-test/t/ps.test
+++ b/mysql-test/t/ps.test
@@ -1807,4 +1807,21 @@ execute stmt using @a;
 show create table t1;
 drop table t1;
 
+#
+# Bug#33798: prepared statements improperly handle large unsigned ints
+#
+--disable_warnings
+drop table if exists t1;
+--enable_warnings
+create table t1 (a bigint unsigned, b bigint(20) unsigned);
+prepare stmt from "insert into t1 values (?,?)";
+set @a= 9999999999999999;
+set @b= 14632475938453979136;
+insert into t1 values (@a, @b);
+select * from t1 where a = @a and b = @b;
+execute stmt using @a, @b;
+select * from t1 where a = @a and b = @b;
+deallocate prepare stmt;
+drop table t1;
+
 --echo End of 5.0 tests.
diff --git a/sql/item.cc b/sql/item.cc
index 713e7709bcb..ffb18054750 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -2580,6 +2580,7 @@ bool Item_param::set_from_user_var(THD *thd, const user_var_entry *entry)
   if (entry && entry->value)
   {
     item_result_type= entry->type;
+    unsigned_flag= entry->unsigned_flag;
     if (strict_type && required_result_type != item_result_type)
       DBUG_RETURN(1);
     switch (item_result_type) {
@@ -2875,7 +2876,10 @@ const String *Item_param::query_val_str(String* str) const
 {
   switch (state) {
   case INT_VALUE:
-    str->set(value.integer, &my_charset_bin);
+    if (unsigned_flag)
+      str->set((ulonglong) value.integer, &my_charset_bin);
+    else
+      str->set(value.integer, &my_charset_bin);
     break;
   case REAL_VALUE:
     str->set(value.real, NOT_FIXED_DEC, &my_charset_bin);