In clinical practice, when the organism has thrombotic and embolic diseases, it is often necessary to apply thrombolytic drugs for their treatment. In clinical practice, there are two types of drugs commonly used to dissolve blood clots, one is urokinase and the other is streptokinase. These two drugs are similar in principle of action, both are fibrinogen activators, which can activate fibrinolytic enzymes in human body, so that fibrinolytic enzymes can break down the formed fibrin thrombus and finally form decomposable fibrin monomers, which can achieve the effect of dissolving thrombus. However, when applying urokinase or streptokinase, we should pay attention to the dosage of the drug. If the dosage is too small, the thrombus cannot be dissolved adequately and the treatment effect will be poor, but if the dosage is too large, bleeding will also easily occur. Urokinase and streptokinase are the most important drugs to dissolve blood clots, but the correct dosage should be used. There are also second- and third-generation clinical thrombolytic agents with greater specificity, higher revascularization rates, and lower bleeding complications. Such as alteplase and ralteplase.