Sub-solid lung nodules have a higher likelihood of malignancy, and depending on their size and morphology can be treated with either regular follow-up or surgery. Lung nodules can be categorized into two groups based on their density, including solid nodules and sub-solid nodules. Sub-solid nodules are further divided into partially solid nodules and ground glass nodules. Among them, partially solid nodules have the highest probability of malignancy, followed by ground glass and solid nodules. If the nodule is smaller than 8mm, CT review can be performed at the 3rd, 6th, 12th and 24th months, and if there is no significant change, then annual review can be performed. If the nodule is larger than 8 mm, 3-month CT examination and empiric antimicrobial therapy are considered appropriately. If the nodule persists after antimicrobial therapy, use of biopsy or surgical excision is recommended. Biopsy or surgical resection may be considered directly if the diameter is greater than 15 mm. When sub-solid pulmonary nodules are found, it is recommended that patients go to regular hospitals in time and listen to the advice of specialized doctors.