The cause of left eyebrow pain may be the interference of physiological factors such as excessive eye use, or it may be caused by pathological reasons such as nerve, ear, nose and throat diseases. 1. Physiological factors: mainly include prolonged overuse of eyes, looking at cell phones, looking at computers, bright light stimulation, anxiety, irregular lifestyle, wearing pupils, etc. These factors will cause fatigue and disorders of periorbital nerves or autonomic nerves, which may lead to the occurrence of left eyebrow pain. 2. Pathologic causes: mainly include neurological diseases and ear, nose and throat system diseases. Neurological disorders can cause lesions of the nerves innervating the left eyebrow, leading to the occurrence of pain symptoms, such as trigeminal neuralgia, supraorbital neuralgia, migraine and other diseases; ear, nose and throat disorders leading to pain, most of them are due to the infection of the shared pathways of the ear, nose and throat, resulting in the spread of inflammation, such as conjunctivitis, sinusitis, sieve sinusitis and so on. Left eyebrow pain may also have other causes, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.