There are many factors affecting the left side of the neck pain: First, overwork, cervical spine muscle damage, it is recommended to pay more attention to rest in life, more activities of the neck every day, pay attention to the protection of the neck. Second, the left side of the neck is cold, may be blowing cold wind, it is recommended to blow less air conditioning, fans, etc., pay attention to the neck warmth. Third, bad sleeping posture, too tired during the day, rest at night without attention, directly fall asleep, it is recommended not to sleep on too high a pillow, to avoid falling pillow, aggravating neck pain. Fourth, cervical spondylosis, may already have cervical spondylosis, not timely treatment resulting in pain on the left side of the neck, it is recommended to carry out local towel hot compresses to slow down the pain, timely hospital for detailed examination, combined with acupuncture methods for treatment.