diff --git a/doc/services/llext/index.rst b/doc/services/llext/index.rst
index ebae211d16d..ea63738ba3c 100644
--- a/doc/services/llext/index.rst
+++ b/doc/services/llext/index.rst
@@ -22,3 +22,5 @@ and introspected to some degree, as well as unloaded when no longer needed.
 
    The LLEXT subsystem requires architecture-specific support. It is currently
    available only on RISC-V, ARM, ARM64, ARC (experimental) and Xtensa cores.
+   Harvard architecture cores that separate code and data paths and have no
+   common memory are not supported.
diff --git a/subsys/llext/Kconfig b/subsys/llext/Kconfig
index 55800dcd0cf..0e3ce5dd57d 100644
--- a/subsys/llext/Kconfig
+++ b/subsys/llext/Kconfig
@@ -5,6 +5,7 @@ menuconfig LLEXT
 	bool "Linkable loadable extensions"
 	select CACHE_MANAGEMENT if DCACHE
 	select KERNEL_WHOLE_ARCHIVE
+	depends on !HARVARD
 	help
 	  Enable the linkable loadable extension subsystem
 
diff --git a/tests/subsys/llext/simple/testcase.yaml b/tests/subsys/llext/simple/testcase.yaml
index 23f31de6d06..bd48a6374f9 100644
--- a/tests/subsys/llext/simple/testcase.yaml
+++ b/tests/subsys/llext/simple/testcase.yaml
@@ -13,6 +13,7 @@ common:
     - qemu_cortex_r5          # ARM Cortex-R5 (ARMv7-R ISA)
     - mps2/an385              # ARM Cortex-M3 (ARMv7-M ISA)
     - mps2/an521/cpu0         # ARM Cortex-M33 (ARMv8-M ISA)
+  filter: not CONFIG_HARVARD
   extra_configs:
     - arch:arm64:CONFIG_LLEXT_HEAP_SIZE=128
   extra_conf_files: