SheetData sheetData = sheet.getJaxbElement().getSheetData(); org.xlsx4j.sml.ObjectFactory factory = org.xlsx4j.jaxb.Context.getsmlObjectFactory(); CTCalcPr ctCalcPr = factory.createCTCalcPr(); ctCalcPr.setCalcMode(STCalcMode.AUTO); pkg.getWorkbookPart().getJaxbElement().setCalcPr(ctCalcPr);