Ascaris larvae or eggs may be found in sputum is a clinical symptom of pulmonary ascariasis, and ascaris larvae or eggs may be found in sputum examination. Ascaris lumbricoides is the most common parasite in humans. The estimated number of people infected with Ascaris lumbricoides worldwide is 1.3 billion. The average infection rate of Ascaris lumbricoides in China is 2.7%-98.4%, and the infection rate in most rural areas of China is more than 60% in heavily endemic areas, and the highest infection is in the age group of 3-10 years. The symptoms of Ascaris larvae or eggs can be found in sputum mainly include mainly chills, fever, chest tightness, itchy throat, dry cough, urticaria, and a few patients can have symptoms of toxic encephalopathy such as asthma, dyspnea, blood in sputum, chest pain and headache, convulsions, and coma. Signs are often absent or there are scattered dry and wet rales in both lungs, and those with toxic encephalopathy may have pupil changes, positive Bartholomew’s sign and Kirsch’s sign. Laboratory tests may show an increase in peripheral blood eosinophils in the early stage of acute mass infection with Ascaris larvae, generally up to 20%-70%, and Ascaris larvae or eggs may be found in sputum. x-ray chest radiographs show scattered, dotted, flocculent or small fuzzy marginal shadows in the lungs. According to the comprehensive analysis of epidemiology, clinical manifestations and laboratory tests, but Ascaris infection is still mainly diagnosed by parasitology.