// Create a new workbook Workbook workbook = new Workbook(); IWorksheet worksheet = workbook.getWorksheets().get(0); //A1:C4 is a single merged cell. worksheet.getRange("A1:C4").merge(); //H5:J5 is a single merged cell. //H6:J6 is a single merged cell. worksheet.getRange("H5:J6").merge(true); //select A1:H5's entire merge area A1:J5, entire merge area is a bounding rectangle. IRange entireMergeArea = worksheet.getRange("A1:H5").getEntireMergeArea(); entireMergeArea.select(); //judge if H5 is a merged cell. if (worksheet.getRange("J5").getMergeCells()) { //set value to the top left cell of the merge area. worksheet.getRange("J5").getEntireMergeArea().get(0, 0).setValue(1); } // Save to an excel file workbook.save("MergeCells.xlsx");