diff --git a/PdfOpt/PdfOptHelper.cs b/PdfOpt/PdfOptHelper.cs
index 8cd8b1b..e367a90 100644
--- a/PdfOpt/PdfOptHelper.cs
+++ b/PdfOpt/PdfOptHelper.cs
@@ -30,7 +30,7 @@ namespace PDFGenerateApi
             using (var stream = new MemoryStream())
             {
                 // 创建 PDF Writer
-                PdfWriter writer = new PdfWriter(stream);
+                PdfWriter writer = new PdfWriter(stream, new WriterProperties().SetCompressionLevel(CompressionConstants.BEST_COMPRESSION));
                 PdfDocument pdf = new PdfDocument(writer);
                 // 设置页面大小为横向 A4
                 PageSize pageSize = PageSize.A4.Rotate();