Abstract: Thrombolysis is an important treatment in critical patients with acute pulmonary embolism (PE). Although meta-analysis has shown that acute PE patients benefit from thrombolysis, the mortality is not reduced when thrombolysis is applied in patients with PE of intermediate risk due to the increased bleeding risk. Guidelines recommend that thrombolysis should be applied in high-risk PE with cardiac arrest, obstructive shock, or persistent hypotension. The most important risk of thrombolysis is bleeding, especially cranial bleeding, which restricts the wide use of thrombolysis. Recombinant tissue-type plasminogen activator is the most widely used thrombolytic agent, which is superior to urokinase and streptokinase. Some studies on reduced-dose thrombolysis achieved advantageous results, but more large-scale studies are needed. Ultrasound-assisted thrombolysis is a widely studied catheter-directed thrombolytic technique, and can be applied in some specific patients.