There are a number of Font related bugs open, this task has been created to track them all.
Incorrect glyphs printed from OpenType PS font when printing on Windows
OpenType font embedding in PostScript / PDF
It looks that text is much bigger when in print preview.
Qt uses the wrong PostScript names when embedding fonts in EPS files on Windows and Cocoa
QPrintPreviewWidget shows strange overpainted characters when previewing QWebPage contents
Wrong character spacing when printing arabic text to PDF output, and wrong text alignment when printing the same text with the same alignment options to a normal printer
Printing one character over the other when 240x144 dpi with LX-300+II using QTextDocument to print html file on Windows
when helvetica is used in a QTextDocument for printing to a PDF then the font is rendered too small on Embedded Linux
Printing a text with font Arial 10 to the Print Preview dialog and to PDF is not consistent.
PDF printengine embeds Déjà vu sans bold in a lousy quality instead on falling back on Arial in such cases.
Fonts are embedded in EPS/PDF files at the wrong scale on Windows, meaning they can't be substituted for the real fonts without changing the apparent size of the text
Qt can crash after exporting a PDF file with QPrinter due to deleted QFontEngines remaining in the QFontCache
Printing UTF-8 HTML with Chinese/Japanese & special symbols are broken
Windows printing of Chinese, Japanese and special symbols is wrong
Wrong font size when printing from QWebView
When printing a QPicture to PDF then the character spacing in the text is not correct
PDF export with OpenType PS fonts puts glyphs at the wrong horizontal positions on Windows
Support for controlling font embedding on Windows and OSX
QtPrintSupport - Bug Triage