diff --git a/tests/bugs/gh_7916_test.py b/tests/bugs/gh_7916_test.py
new file mode 100644
index 00000000..152c9b3e
--- /dev/null
+++ b/tests/bugs/gh_7916_test.py
@@ -0,0 +1,54 @@
+#coding:utf-8
+
+"""
+ID:          issue-7916
+ISSUE:       https://github.com/FirebirdSQL/firebird/issues/7916
+TITLE:       Query issue conversion error from string
+NOTES:
+    [10.02.2024] pzotov
+    Confirmed bug on 6.0.0.250
+    Checked on 6.0.0.257.
+"""
+
+import pytest
+from firebird.qa import *
+
+db = db_factory()
+
+test_script = """
+    recreate table session$test (sess_user char(63));
+    recreate table staff$test (staffid smallint, primary key (staffid) using index staff$test_staffid);
+
+    insert into session$test values ('TEST');
+    insert into session$test values ('1');
+    insert into staff$test values (1);
+
+    set list on;
+    -- set explain on;
+
+    select sess.sess_user, stf.staffid 
+      from session$test sess
+           left join rdb$database rdb
+              on 1 = 1
+           left join staff$test stf
+              on trim(sess.sess_user) similar to '[0-9]+' 
+             and stf.staffid = cast(trim(sess.sess_user) as smallint)
+    order by stf.staffid + 0
+    ;
+"""
+
+act = isql_act('db', test_script, substitutions = [('[ \t]+', ' ')])
+
+expected_stdout = """
+    SESS_USER TEST
+    STAFFID <null>
+
+    SESS_USER 1
+    STAFFID 1
+"""
+
+@pytest.mark.version('>=6.0')
+def test_1(act: Action):
+    act.expected_stdout = expected_stdout
+    act.execute(combine_output = True)
+    assert act.clean_stdout == act.clean_expected_stdout