Levodopa is one of the most commonly used dopamine replacement therapies in clinical practice, the mechanism of action of levodopamine is mainly by supplementing the dopamine deficiency in the substantia nigra striata, it is one of the most important therapeutic treatments for Parkinson’s disease, because dopamine is not able to pass through the blood-brain barrier, the clinical use of replacement therapies to supplement the levodopa of its precursor, when levodopa enters the brain, it is uptaken by the dopaminergic neurons, and then converted to dopamine to function. Levodopa can basically improve all the clinical symptoms of Parkinson’s disease patients in terms of treatment, such as increased muscle tone, limb tremor, and slow movement. However, levodopa treatment should start with a small dose, initially 125mg orally three times a day, and gradually increase the dose every other week.