Whether or not a 0.3cm gastric polyp is dangerous cannot be generalized, but needs to be combined with the nature of the polyp, and whether or not there are symptoms and other related. Most gastric polyps are fundic glandular polyps or hyperplastic polyps, it is generally believed that more than 3cm ~ 4cm polyps have the possibility of malignant transformation, while for 0.3cm gastric polyps are relatively not serious, do not have to worry too much, you can continue to observe. But for rare gastric polyps, such as acid gland, mucosal adenomas, the possibility of malignant transformation is greater, it is more dangerous. It is also dangerous when the location of the polyp causes severe stomach discomfort. It is important to note that when gastric polyps are found, they should be seen by a doctor in a timely manner to determine their nature and severity, rather than relying on their size alone to determine whether they are dangerous or not.