diff --git a/lv_core/lv_i18n.c b/lv_core/lv_i18n.c
index 8d7cf1b66..1a75869de 100644
--- a/lv_core/lv_i18n.c
+++ b/lv_core/lv_i18n.c
@@ -23,7 +23,7 @@
 /**********************
  *  STATIC PROTOTYPES
  **********************/
-static const void * lv_i18n_get_text_core(lv_i18n_trans_t * trans, const char * msg_id);
+static const void * lv_i18n_get_text_core(const lv_i18n_trans_t * trans, const char * msg_id);
 
 /**********************
  *  STATIC VARIABLES
@@ -238,7 +238,7 @@ const void *  lv_i18n_get_current_local(void)
  *   STATIC FUNCTIONS
  **********************/
 
-static const void * lv_i18n_get_text_core(lv_i18n_trans_t * trans, const char * msg_id)
+static const void * lv_i18n_get_text_core(const lv_i18n_trans_t * trans, const char * msg_id)
 {
     uint16_t i;
     for(i = 0; trans[i].msg_id != NULL; i++) {
diff --git a/lv_core/lv_i18n.h b/lv_core/lv_i18n.h
index 043a49349..894213bc0 100644
--- a/lv_core/lv_i18n.h
+++ b/lv_core/lv_i18n.h
@@ -49,12 +49,12 @@ typedef struct {
 
 typedef struct {
     const char * name;                                      /*E.g. "en_GB"*/
-    lv_i18n_trans_t * simple;                               /*Translations of simple texts where no plurals are used*/
-    lv_i18n_trans_t * plurals[_LV_I18N_PLURAL_TYPE_NUM];    /*Translations of the plural forms*/
+    const lv_i18n_trans_t * simple;                               /*Translations of simple texts where no plurals are used*/
+    const lv_i18n_trans_t * plurals[_LV_I18N_PLURAL_TYPE_NUM];    /*Translations of the plural forms*/
     uint8_t (*plural_rule)(int32_t num);                    /*Function pointer to get the correct plural form for a number*/
 }lv_i18n_lang_t;
 
-typedef lv_i18n_lang_t * lv_i18n_lang_pack_t;
+typedef const lv_i18n_lang_t * lv_i18n_lang_pack_t;
 
 /**********************
  * GLOBAL PROTOTYPES