Lung cancer can lead to pleural effusion, especially when combined with pleural metastasis, 95% of which are pleural metastasis of lung cancer. Simple puncture and drainage cannot solve the fundamental problem, and systemic treatment is needed to eliminate pleural effusion. Pleural effusion can be treated by intrathoracic chemotherapy with systemic treatment. Cisplatin, bleomycin and anti-tumor angiogenic drugs, such as vascular endothelial inhibitors, can be chosen for infusion chemotherapy, which can help eliminate pleural effusion once a week. Systemic treatment for lung cancer on top of this, squamous or adenocarcinoma can be treated with chemotherapy or targeted drugs, and immune checkpoint inhibitors can be beneficial for fluid accumulation in the lung.