diff --git a/src/zcl_common_class.clas.abap b/src/zcl_common_class.clas.abap
index 1352a90..a593b73 100644
--- a/src/zcl_common_class.clas.abap
+++ b/src/zcl_common_class.clas.abap
@@ -20,6 +20,158 @@ ENDCLASS.
 CLASS ZCL_COMMON_CLASS IMPLEMENTATION.
 
 
-  method UPLOAD_EXCEL_TO_ITAB.
-  endmethod.
+  METHOD upload_excel_to_itab.
+    DATA: lt_bin        TYPE solix_tab,
+          lv_xstring    TYPE xstring,
+          lv_filename   TYPE string,
+          lo_excel      TYPE REF TO cl_fdt_xl_spreadsheet,
+          lt_worksheets TYPE if_fdt_doc_spreadsheet=>t_worksheet_names,
+          lv_sheet_name TYPE string,
+          lr_data_ref   TYPE REF TO data.
+
+    DATA: lt_row TYPE ty_row,
+          lv_idx TYPE i.
+
+    FIELD-SYMBOLS: <lt_sheet> TYPE STANDARD TABLE,
+                   <ls_sheet> TYPE any,
+                   <lv_cell>  TYPE any.
+
+    " 파일 선택
+    DATA: lt_file_table TYPE filetable,
+          lv_rc         TYPE i.
+
+    CALL METHOD cl_gui_frontend_services=>file_open_dialog
+      EXPORTING
+        default_extension = 'XLSX'
+        file_filter       = 'Excel Files (*.xlsx)|*.xlsx'
+      CHANGING
+        file_table        = lt_file_table
+        rc                = lv_rc
+      EXCEPTIONS
+        OTHERS            = 1.
+
+    IF sy-subrc <> 0 OR lv_rc = 0.
+      MESSAGE '파일 선택이 취소되었습니다.' TYPE 'S'.
+      RETURN.
+    ENDIF.
+
+    READ TABLE lt_file_table INDEX 1 INTO DATA(ls_file).
+    IF sy-subrc <> 0.
+      MESSAGE '선택한 파일 정보를 읽을 수 없습니다.' TYPE 'E'.
+      RETURN.
+    ENDIF.
+
+    lv_filename = ls_file-filename.
+
+    " 엑셀 파일 바이너리 업로드
+    CALL METHOD cl_gui_frontend_services=>gui_upload
+      EXPORTING
+        filename                = lv_filename
+        filetype                = 'BIN'
+      IMPORTING
+        filelength              = DATA(lv_filelength)
+      CHANGING
+        data_tab                = lt_bin
+      EXCEPTIONS
+        file_open_error         = 1
+        file_read_error         = 2
+        no_batch                = 3
+        gui_refuse_filetransfer = 4
+        invalid_type            = 5
+        no_authority            = 6
+        unknown_error           = 7
+        bad_data_format         = 8
+        header_not_allowed      = 9
+        separator_not_allowed   = 10
+        header_too_long         = 11
+        unknown_dp_error        = 12
+        access_denied           = 13
+        dp_out_of_memory        = 14
+        disk_full               = 15
+        dp_timeout              = 16
+        not_supported_by_gui    = 17
+        error_no_gui            = 18
+        OTHERS                  = 19.
+
+    IF sy-subrc <> 0.
+      MESSAGE '엑셀 파일 업로드 중 오류가 발생했습니다.' TYPE 'E'.
+      RETURN.
+    ENDIF.
+
+    " 바이너리 -> XSTRING 변환
+    CALL FUNCTION 'SCMS_BINARY_TO_XSTRING'
+      EXPORTING
+        input_length = lv_filelength
+      IMPORTING
+        buffer       = lv_xstring
+      TABLES
+        binary_tab   = lt_bin
+      EXCEPTIONS
+        failed       = 1
+        OTHERS       = 2.
+
+    IF sy-subrc <> 0.
+      MESSAGE '엑셀 파일 변환 중 오류가 발생했습니다.' TYPE 'E'.
+      RETURN.
+    ENDIF.
+
+    "---------------------------------------------------------------"
+    " 4. XLSX 파싱 및 첫 번째 시트 읽기
+    "---------------------------------------------------------------"
+    TRY.
+        CREATE OBJECT lo_excel
+          EXPORTING
+            document_name = lv_filename
+            xdocument     = lv_xstring.
+
+        IF lo_excel IS INITIAL.
+          MESSAGE '엑셀 객체 생성에 실패했습니다.' TYPE 'E'.
+          EXIT.
+        ENDIF.
+
+        lo_excel->if_fdt_doc_spreadsheet~get_worksheet_names(
+          IMPORTING
+            worksheet_names = lt_worksheets ).
+
+        READ TABLE lt_worksheets INTO lv_sheet_name INDEX 1.
+        IF sy-subrc <> 0.
+          MESSAGE '워크시트를 찾을 수 없습니다.' TYPE 'E'.
+          EXIT.
+        ENDIF.
+
+        lr_data_ref = lo_excel->if_fdt_doc_spreadsheet~get_itab_from_worksheet(
+                        lv_sheet_name ).
+
+        rr_data = lr_data_ref.
+
+*        ASSIGN lr_data_ref->* TO <lt_sheet>.
+*        IF <lt_sheet> IS NOT ASSIGNED.
+*          MESSAGE '시트 데이터를 읽을 수 없습니다.' TYPE 'E'.
+*          EXIT.
+*        ENDIF.
+
+      CATCH cx_root.
+        MESSAGE '엑셀 파일 해석 중 오류가 발생했습니다.' TYPE 'E'.
+        EXIT.
+    ENDTRY.
+
+
+*    LOOP AT <lt_sheet> ASSIGNING <ls_sheet>.
+*      CLEAR lt_row.
+*
+*      lv_idx = 1.
+*      DO.
+*        ASSIGN COMPONENT lv_idx OF STRUCTURE <ls_sheet> TO <lv_cell>.
+*        IF sy-subrc <> 0.
+*          EXIT.
+*        ENDIF.
+*
+*        APPEND CONV string( <lv_cell> ) TO lt_row.
+*        lv_idx = lv_idx + 1.
+*      ENDDO.
+*
+*      APPEND lt_row TO et_data.
+*    ENDLOOP.
+
+  ENDMETHOD.
 ENDCLASS.