Single or multiple entry visa required for me and my companion

My traveling companion and myself are Canadian citizens entering Mainland China at Kunming, Yunnan then flying to Guilin, Guangxi. From there we will travel overland boat, bus, train to Hong Kong for our exit flight. Total length of stay will be 20 days.
Confused about whether we need to apply for a single or two entry type. Does traveling from Mainland China to Hong Kong constitute a separate entry? We will NOT be re-entering Mainland China from Hong Kong, that is our exit point.
We have our flights entering China at Kunming and exiting from Hong Kong booked and confirmed.