diff --git a/CHANGES/7014.bugfix b/CHANGES/7014.bugfix
new file mode 100644
index 00000000000..34a4668288f
--- /dev/null
+++ b/CHANGES/7014.bugfix
@@ -0,0 +1 @@
+Fixed bug when using ``TCPConnector`` with ``ttl_dns_cache=0``.
diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index c1651d50299..71910b8bae5 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -147,6 +147,8 @@ Illia Volochii
 Ilya Chichak
 Ilya Gruzinov
 Ingmar Steen
+Ivan Lakovic
+Ivan Larin
 Jacob Champion
 Jaesung Lee
 Jake Davis
diff --git a/aiohttp/connector.py b/aiohttp/connector.py
index 81b71313931..5c55669ec39 100644
--- a/aiohttp/connector.py
+++ b/aiohttp/connector.py
@@ -709,13 +709,13 @@ def __contains__(self, host: object) -> bool:
     def add(self, key: Tuple[str, int], addrs: List[Dict[str, Any]]) -> None:
         self._addrs_rr[key] = (cycle(addrs), len(addrs))
 
-        if self._ttl:
+        if self._ttl is not None:
             self._timestamps[key] = monotonic()
 
     def remove(self, key: Tuple[str, int]) -> None:
         self._addrs_rr.pop(key, None)
 
-        if self._ttl:
+        if self._ttl is not None:
             self._timestamps.pop(key, None)
 
     def clear(self) -> None:
diff --git a/tests/test_connector.py b/tests/test_connector.py
index 0b992df98cb..7d8dc7e31d0 100644
--- a/tests/test_connector.py
+++ b/tests/test_connector.py
@@ -2165,10 +2165,27 @@ def test_not_expired_ttl(self) -> None:
         dns_cache_table.add("localhost", ["127.0.0.1"])
         assert not dns_cache_table.expired("localhost")
 
-    async def test_expired_ttl(self, loop) -> None:
-        dns_cache_table = _DNSCacheTable(ttl=0.01)
+    def test_expired_ttl(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        dns_cache_table = _DNSCacheTable(ttl=1)
+        monkeypatch.setattr("aiohttp.connector.monotonic", lambda: 1)
         dns_cache_table.add("localhost", ["127.0.0.1"])
-        await asyncio.sleep(0.02)
+        monkeypatch.setattr("aiohttp.connector.monotonic", lambda: 2)
+        assert not dns_cache_table.expired("localhost")
+        monkeypatch.setattr("aiohttp.connector.monotonic", lambda: 3)
+        assert dns_cache_table.expired("localhost")
+
+    def test_never_expire(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        dns_cache_table = _DNSCacheTable(ttl=None)
+        monkeypatch.setattr("aiohttp.connector.monotonic", lambda: 1)
+        dns_cache_table.add("localhost", ["127.0.0.1"])
+        monkeypatch.setattr("aiohttp.connector.monotonic", lambda: 10000000)
+        assert not dns_cache_table.expired("localhost")
+
+    def test_always_expire(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        dns_cache_table = _DNSCacheTable(ttl=0)
+        monkeypatch.setattr("aiohttp.connector.monotonic", lambda: 1)
+        dns_cache_table.add("localhost", ["127.0.0.1"])
+        monkeypatch.setattr("aiohttp.connector.monotonic", lambda: 1.00001)
         assert dns_cache_table.expired("localhost")
 
     def test_next_addrs(self, dns_cache_table) -> None: