I have carried out a psycholinguistic experiment to show that there are are 6 tones in Cantonese speakers' mind. Please refer to http://www.patrickchu.net/uploads/9/0/5/3/9053324/2011_plrt_paper.pdf for the detailed experiment. Patrick Chu, PhD (http://www.patrickchu.net)

As I remember,, its 8. but the website shows its 6. http://baike.baidu.com/view/197269.htm check it out. I speak Cantonese but I have never learned the tones.

actually it has 6 tones. some articles may say it has 9 tones. but in linguistics, the other 3 tones are not considered "tone", they are "入声". so Guangzhou cantonese has 九声六调.