diff --git a/stix2/__init__.py b/stix2/__init__.py
index c2aae2e..e69a5c3 100644
--- a/stix2/__init__.py
+++ b/stix2/__init__.py
@@ -37,7 +37,8 @@ from .patterns import (AndBooleanExpression, AndObservationExpression,
                        OrObservationExpression, ParentheticalExpression,
                        QualifiedObservationExpression,
                        ReferenceObjectPathComponent, RepeatQualifier,
-                       StartStopQualifier, StringConstant, WithinQualifier)
+                       StartStopQualifier, StringConstant, TimestampConstant,
+                       WithinQualifier)
 from .sdo import (AttackPattern, Campaign, CourseOfAction, CustomObject,
                   Identity, Indicator, IntrusionSet, Malware, ObservedData,
                   Report, ThreatActor, Tool, Vulnerability)
diff --git a/stix2/patterns.py b/stix2/patterns.py
index d861144..7858146 100644
--- a/stix2/patterns.py
+++ b/stix2/patterns.py
@@ -19,6 +19,14 @@ class StringConstant(_Constant):
         return "'%s'" % escape_quotes_and_backslashes(self.value)
 
 
+class TimestampConstant(_Constant):
+    def __init__(self, value):
+        self.value = value
+
+    def __str__(self):
+        return "'%s'" % escape_quotes_and_backslashes(self.value)
+
+
 class IntegerConstant(_Constant):
     def __init__(self, value):
         try: