In October 2000, Mok made her Junior Grand Prix (JGP) debut, placing fourth in Germany before winning bronze in the Czech Republic. In November, she won a senior international medal – silver at the Golden Spin of Zagreb. Around 2000, she developed a pinched nerve in her back. She was selected to compete at the 2001 World Junior Championships in Sofia, Bulgaria. She placed tenth in her qualifying group but withdrew before the short program.