diff --git a/tuf/api/metadata.py b/tuf/api/metadata.py
index 6c8b307161..23ed1fff43 100644
--- a/tuf/api/metadata.py
+++ b/tuf/api/metadata.py
@@ -506,6 +506,8 @@ def __init__(
                 f"keyids should be a list of unique strings,"
                 f" instead got {keyids}"
             )
+        if threshold < 1:
+            raise ValueError("threshold should be at least 1!")
         self.keyids = keyids_set
         self.threshold = threshold
         self.unrecognized_fields: Mapping[str, Any] = unrecognized_fields or {}