diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 66013b9fa9..b51a42d9f3 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -51,6 +51,7 @@ Changed
   set to 3 seconds. Previously a default value of 30 seconds was used which means that for many
   connection related errors, our code would first wait for this timeout to be reached (30 seconds)
   before returning error to the end user. #4834
+* Upgrade ``pymongo`` to the latest stable version (``3.10.0.``). #4835 (improvement)
 
 Fixed
 ~~~~~
diff --git a/fixed-requirements.txt b/fixed-requirements.txt
index 7f9222282c..3ac7f05d29 100644
--- a/fixed-requirements.txt
+++ b/fixed-requirements.txt
@@ -18,7 +18,7 @@ requests[security]==2.22.0
 apscheduler==3.6.3
 gitpython==2.1.11
 jsonschema==2.6.0
-pymongo==3.7.2
+pymongo==3.10.0
 mongoengine==0.18.2
 passlib==1.7.1
 lockfile==0.12.2
diff --git a/requirements.txt b/requirements.txt
index 992ff32fd4..5e6b631ee4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -40,7 +40,7 @@ prettytable
 prompt-toolkit==1.0.15
 psutil==5.6.3
 pyinotify==0.9.6
-pymongo==3.7.2
+pymongo==3.10.0
 pyrabbit
 python-dateutil==2.8.0
 python-editor==1.0.4
diff --git a/st2api/requirements.txt b/st2api/requirements.txt
index be6ea74399..735c125d26 100644
--- a/st2api/requirements.txt
+++ b/st2api/requirements.txt
@@ -13,5 +13,5 @@ kombu==4.6.6
 mongoengine==0.18.2
 oslo.config<1.13,>=1.12.1
 oslo.utils<=3.37.0,>=3.36.2
-pymongo==3.7.2
+pymongo==3.10.0
 six==1.13.0
diff --git a/st2auth/requirements.txt b/st2auth/requirements.txt
index 315a21db3c..9d20e81a42 100644
--- a/st2auth/requirements.txt
+++ b/st2auth/requirements.txt
@@ -11,6 +11,6 @@ git+https://github.com/StackStorm/st2-auth-backend-flat-file.git@master#egg=st2-
 gunicorn==19.9.0
 oslo.config<1.13,>=1.12.1
 passlib==1.7.1
-pymongo==3.7.2
+pymongo==3.10.0
 six==1.13.0
 stevedore==1.30.1
diff --git a/st2common/requirements.txt b/st2common/requirements.txt
index 991358ed9d..95d94276ba 100644
--- a/st2common/requirements.txt
+++ b/st2common/requirements.txt
@@ -23,7 +23,7 @@ mongoengine==0.18.2
 networkx==1.11
 oslo.config<1.13,>=1.12.1
 paramiko==2.6.0
-pymongo==3.7.2
+pymongo==3.10.0
 python-dateutil==2.8.0
 python-statsd==2.1.0
 pyyaml==5.1.2
diff --git a/st2common/st2common/models/db/__init__.py b/st2common/st2common/models/db/__init__.py
index d8f6f48257..098a8e45da 100644
--- a/st2common/st2common/models/db/__init__.py
+++ b/st2common/st2common/models/db/__init__.py
@@ -306,6 +306,9 @@ def db_cleanup(db_name, db_host, db_port, username=None, password=None,
 
 def _get_ssl_kwargs(ssl=False, ssl_keyfile=None, ssl_certfile=None, ssl_cert_reqs=None,
                     ssl_ca_certs=None, authentication_mechanism=None, ssl_match_hostname=True):
+    # NOTE: In pymongo 3.9.0 some of the ssl related arguments have been renamed -
+    # https://api.mongodb.com/python/current/changelog.html#changes-in-version-3-9-0
+    # Old names still work, but we should eventually update to new argument names.
     ssl_kwargs = {
         'ssl': ssl,
     }
diff --git a/st2stream/requirements.txt b/st2stream/requirements.txt
index 890b64f2c1..7a920a843f 100644
--- a/st2stream/requirements.txt
+++ b/st2stream/requirements.txt
@@ -12,5 +12,5 @@ kombu==4.6.6
 mongoengine==0.18.2
 oslo.config<1.13,>=1.12.1
 oslo.utils<=3.37.0,>=3.36.2
-pymongo==3.7.2
+pymongo==3.10.0
 six==1.13.0