diff --git a/monkey/tests/unit_tests/monkey_island/cc/resources/test_configuration_import.py b/monkey/tests/unit_tests/monkey_island/cc/resources/test_configuration_import.py
index ed1d908cf..e9672ebdf 100644
--- a/monkey/tests/unit_tests/monkey_island/cc/resources/test_configuration_import.py
+++ b/monkey/tests/unit_tests/monkey_island/cc/resources/test_configuration_import.py
@@ -13,6 +13,7 @@ def test_is_config_encrypted__json(monkey_config_json):
     assert not ConfigurationImport.is_config_encrypted(monkey_config_json)
 
 
+@pytest.mark.slow
 def test_is_config_encrypted__ciphertext(monkey_config_json):
     encrypted_config = encrypt_string(monkey_config_json, PASSWORD)
     assert ConfigurationImport.is_config_encrypted(encrypted_config)
diff --git a/monkey/tests/unit_tests/monkey_island/cc/services/attack/test_mitre_api_interface.py b/monkey/tests/unit_tests/monkey_island/cc/services/attack/test_mitre_api_interface.py
index b6b9acbc7..f93afc8d5 100644
--- a/monkey/tests/unit_tests/monkey_island/cc/services/attack/test_mitre_api_interface.py
+++ b/monkey/tests/unit_tests/monkey_island/cc/services/attack/test_mitre_api_interface.py
@@ -1,6 +1,9 @@
+import pytest
+
 from monkey_island.cc.services.attack.mitre_api_interface import MitreApiInterface
 
 
+@pytest.mark.slow
 def test_get_all_mitigations():
     mitigations = MitreApiInterface.get_all_mitigations()
     assert len(mitigations.items()) >= 282
diff --git a/monkey/tests/unit_tests/monkey_island/cc/services/utils/test_config_encryption.py b/monkey/tests/unit_tests/monkey_island/cc/services/utils/test_config_encryption.py
index 086b30109..fd3191f50 100644
--- a/monkey/tests/unit_tests/monkey_island/cc/services/utils/test_config_encryption.py
+++ b/monkey/tests/unit_tests/monkey_island/cc/services/utils/test_config_encryption.py
@@ -16,21 +16,25 @@ PASSWORD = "hello123"
 INCORRECT_PASSWORD = "goodbye321"
 
 
+@pytest.mark.slow
 def test_encrypt_decrypt_string(monkey_config_json):
     encrypted_config = encrypt_string(monkey_config_json, PASSWORD)
     assert decrypt_ciphertext(encrypted_config, PASSWORD) == monkey_config_json
 
 
+@pytest.mark.slow
 def test_decrypt_string__wrong_password(monkey_config_json):
     with pytest.raises(InvalidCredentialsError):
         decrypt_ciphertext(VALID_CIPHER_TEXT, INCORRECT_PASSWORD)
 
 
+@pytest.mark.slow
 def test_decrypt_string__malformed_corrupted():
     with pytest.raises(ValueError):
         decrypt_ciphertext(MALFORMED_CIPHER_TEXT_CORRUPTED, PASSWORD)
 
 
+@pytest.mark.slow
 def test_decrypt_string__no_password(monkey_config_json):
     with pytest.raises(InvalidCredentialsError):
         decrypt_ciphertext(VALID_CIPHER_TEXT, "")
diff --git a/pyproject.toml b/pyproject.toml
index 319c4cc1f..05c8dfe81 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,6 +21,7 @@ log_cli_format = "%(asctime)s [%(levelname)s] %(module)s.%(funcName)s.%(lineno)d
 log_cli_date_format = "%H:%M:%S"
 addopts = "-v --capture=sys tests/unit_tests"
 norecursedirs = "node_modules dist"
+markers = ["slow: mark test as slow"]
 
 [tool.vulture]
 exclude = ["monkey/monkey_island/cc/ui/", "monkey/tests/"]