Gastroparesis (GP) is a disease defined by delayed gastric emptying and dyspeptic symptoms, and it can be associated with the presence of various complications, such as diabetes mellitus, postoperative stomach, and Parkinson’s disease. Because GP is basically defined by delayed gastric emptying, measuring gastric emptying is mandatory for diagnosis. However, gastric emptying tests with a solid meal are not commonly performed in many countries besides North America. As a result, the term GP is primarily used in North America and is seldom employed in other regions, including Asian countries. Patients with GP have symptoms such as early satiety, postprandial fullness, nausea, vomitingVomiting, and abdominal pain. We should be careful to differentiate between idiopathic GP and functional dyspepsia (FD)Functional dyspepsia (FD) that present chronic dyspeptic symptoms without organic, systemic, or metabolic diseases. However, these two conditions have different features of symptoms. GP often presents with nausea and vomitingVomiting, whereas FD Functional dyspepsia (FD)rarely includes these symptoms, particularly vomitingVomiting. Such symptoms are thought to reflect a relatively strong delay of gastric emptying. Although chronic nausea and vomitingVomiting are still rare in Japan, the potential increase in GP patients should be considered due to rising diabetesDiabetes mellitus and Parkinson’s disease cases.