Calcium oxalate crystals are a substance produced by the combination of calcium in the body and oxalic acid in food. Calcium oxalate crystals are mainly a result of high levels of calcium oxalate in the urine, which may be related to your daily diet. If you eat a lot of food containing oxalic acid and calcium, such as spinach, soy products, chocolate, dairy products, etc., some calcium oxalate is not easily absorbed by the body and calcium oxalate crystals will be formed. Calcium oxalate is prone to form crystals in the body, which can easily lead to urinary or biliary tract stones. Calcium oxalate crystals plus indicate a relatively high concentration of calcium oxalate in the body. Patients can appropriately reduce the intake of vegetables, life can be by paying attention to drink more water, so as to promote the discharge of calcium oxalate.