diff --git a/mm/mm_heap/mm_initialize.c b/mm/mm_heap/mm_initialize.c
index 62759e9586..0801eae5d5 100644
--- a/mm/mm_heap/mm_initialize.c
+++ b/mm/mm_heap/mm_initialize.c
@@ -165,17 +165,23 @@ void mm_initialize(FAR struct mm_heap_s *heap, FAR void *heapstart,
                    size_t heapsize)
 {
   FAR struct mm_heap_impl_s *heap_impl;
-  int i;
+  uintptr_t                  heap_adj;
+  int                        i;
 
   minfo("Heap: start=%p size=%zu\n", heapstart, heapsize);
 
+  /* First ensure the memory to be used is aligned */
+
+  heap_adj  = MM_ALIGN_UP((uintptr_t) heapstart);
+  heapsize -= heap_adj - (uintptr_t) heapstart;
+
   /* Reserve a block space for mm_heap_impl_s context */
 
   DEBUGASSERT(heapsize > sizeof(struct mm_heap_impl_s));
-  heap->mm_impl = (FAR struct mm_heap_impl_s *)heapstart;
+  heap->mm_impl = (FAR struct mm_heap_impl_s *)heap_adj;
   heap_impl = heap->mm_impl;
   heapsize -= sizeof(struct mm_heap_impl_s);
-  heapstart = (FAR char *)heapstart + sizeof(struct mm_heap_impl_s);
+  heapstart = (FAR char *)heap_adj + sizeof(struct mm_heap_impl_s);
 
   /* The following two lines have cause problems for some older ZiLog
    * compilers in the past (but not the more recent).  Life is easier if we