private void OnPrintPage(object sender, PrintPageEventArgs e)
{
            using (var page = this.pdfViewer.Document.Pages[this.nextToPrintPageIndex])
            {
                // Printable area given in hundredths of an inch
                var fitSize = new System.Windows.Size(
                    (int)(e.PageSettings.PrintableArea.Width / 100 * e.Graphics.DpiX),
                    (int)(e.PageSettings.PrintableArea.Height / 100 * e.Graphics.DpiY));

                // Get page's size
                var pageSize = new System.Windows.Size(
                    (int)page.Width / 72.0f * e.Graphics.DpiX,
                    (int)page.Height / 72.0f * e.Graphics.DpiY);

                //If page was rotated in original file, then we need to "rotate the paper in printer". 
                //For that just swap the width and height of the paper.
                if (page.OriginalRotation == PageRotate.Rotate270 || page.OriginalRotation == PageRotate.Rotate90)
                    fitSize = new System.Windows.Size(fitSize.Height, fitSize.Width);

                //Calculate the page's size fitted to the paper's size.  
                var rSize = GetRenderSize(pageSize, fitSize);

                using (PdfBitmap bmp = new PdfBitmap((int)rSize.Width, (int)rSize.Height, true))
                {
                    //Render to PdfBitmap using page's Render method with FPDF_PRINTING flag.
                    page.RenderEx
                        (bmp,
                        0,
                        0,
                        (int)rSize.Width,
                        (int)rSize.Height,
                        PageRotate.Normal,
                        RenderFlags.FPDF_PRINTING | RenderFlags.FPDF_ANNOT);

                    //Rotates the PdfBitmap image depending on the orientation of the page
                    if (PageRotation(page) == PageRotate.Rotate270)
                        bmp.Image.RotateFlip(RotateFlipType.Rotate270FlipNone);
                    else if (PageRotation(page) == PageRotate.Rotate180)
                        bmp.Image.RotateFlip(RotateFlipType.Rotate180FlipNone);
                    else if (PageRotation(page) == PageRotate.Rotate90)
                        bmp.Image.RotateFlip(RotateFlipType.Rotate90FlipNone);

                    //Set DPI of the image same as the printer's DPI
                    (bmp.Image as Bitmap).SetResolution(e.Graphics.DpiX, e.Graphics.DpiY);
                    //Draw rendered image to printer's graphics surface
                    e.Graphics.DrawImage(bmp.Image, 0, 0);
                }

                if (this.nextToPrintPageIndex < this.lastToPrintPageIndex)
                {
                    this.nextToPrintPageIndex += 1;
                    e.HasMorePages = true;
                }
            }
}

var doc = PdfDocument.Load(@"d:\1\Default Report.pdf");

//Show standard print dialog
var printDoc = new PdfPrintDocument(doc);
var dlg = new PrintDialog();
dlg.AllowCurrentPage = true;
dlg.AllowSomePages = true;
dlg.UseEXDialog = true;
dlg.Document = printDoc;
if (dlg.ShowDialog() == DialogResult.OK)
{
	try
	{
		dlg.Document.Print();
	}
	catch (Win32Exception)
	{
		//Printing was canceled
	}
}