diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py
index 7f305dcc0d9..d2f1816cb8a 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py
@@ -18,7 +18,6 @@
 import random
 import threading
 from contextlib import contextmanager
-from numbers import Number
 from types import TracebackType
 from typing import Iterator, Optional, Sequence, Tuple, Type
 
@@ -233,12 +232,16 @@ def set_attribute(self, key: str, value: types.AttributeValue) -> None:
             logger.warning("Setting attribute on ended span.")
             return
 
+        if not key:
+            logger.warning("invalid key (empty or null)")
+            return
+
         if isinstance(value, Sequence):
             error_message = self._check_attribute_value_sequence(value)
             if error_message is not None:
                 logger.warning("%s in attribute value sequence", error_message)
                 return
-        elif not isinstance(value, (bool, str, Number, Sequence)):
+        elif not isinstance(value, (bool, str, int, float)):
             logger.warning("invalid type for attribute value")
             return
 
@@ -254,10 +257,7 @@ def _check_attribute_value_sequence(sequence: Sequence) -> Optional[str]:
 
         first_element_type = type(sequence[0])
 
-        if issubclass(first_element_type, Number):
-            first_element_type = Number
-
-        if first_element_type not in (bool, str, Number):
+        if first_element_type not in (bool, str, int, float):
             return "invalid type"
 
         for element in sequence:
diff --git a/opentelemetry-sdk/tests/trace/test_trace.py b/opentelemetry-sdk/tests/trace/test_trace.py
index 188c019acc1..2a50f88c258 100644
--- a/opentelemetry-sdk/tests/trace/test_trace.py
+++ b/opentelemetry-sdk/tests/trace/test_trace.py
@@ -391,7 +391,7 @@ def test_attributes(self):
 
             root.set_attribute("empty-list", [])
             root.set_attribute("list-of-bools", [True, True, False])
-            root.set_attribute("list-of-numerics", [123, 3.14, 0])
+            root.set_attribute("list-of-numerics", [123, 314, 0])
 
             self.assertEqual(len(root.attributes), 10)
             self.assertEqual(root.attributes["component"], "http")
@@ -409,7 +409,7 @@ def test_attributes(self):
                 root.attributes["list-of-bools"], [True, True, False]
             )
             self.assertEqual(
-                root.attributes["list-of-numerics"], [123, 3.14, 0]
+                root.attributes["list-of-numerics"], [123, 314, 0]
             )
 
         attributes = {
@@ -440,6 +440,9 @@ def test_invalid_attribute_values(self):
                 "list-with-non-primitive-data-type", [dict(), 123]
             )
 
+            root.set_attribute("", 123)
+            root.set_attribute(None, 123)
+
             self.assertEqual(len(root.attributes), 0)
 
     def test_check_sequence_helper(self):
@@ -458,8 +461,18 @@ def test_check_sequence_helper(self):
             ),
             "different type",
         )
+        self.assertEqual(
+            trace.Span._check_attribute_value_sequence([1, 2, 3.4, 5]),
+            "different type",
+        )
+        self.assertIsNone(
+            trace.Span._check_attribute_value_sequence([1, 2, 3, 5])
+        )
+        self.assertIsNone(
+            trace.Span._check_attribute_value_sequence([1.2, 2.3, 3.4, 4.5])
+        )
         self.assertIsNone(
-            trace.Span._check_attribute_value_sequence([1, 2, 3.4, 5])
+            trace.Span._check_attribute_value_sequence([True, False])
         )
         self.assertIsNone(
             trace.Span._check_attribute_value_sequence(["ss", "dw", "fw"])