Good electromagnetic interference (EMI) shielding performance, lightweight, and excellent heat resistance are important technical requirements for practical applications of EMI shielding materials, especially in areas of aircraft, aerospace, and automobiles. Herein, a lightweight and robust carbon nanotube (CNT)/polyimide (PI) foam was developed for efficient and heat-resistant EMI shielding. Thanks to the perfect CNT conductive networks, the CNT/PI foam with a density of only 32.1 mg cm-3 achieves a high EMI shielding effectiveness (EMI SE) of 41.1 dB, which is one of the highest value among previously reported CNT/polymer foams. The CNT/PI foam also achieves the absorption coefficient (A) up to 82.3%, which was impressively in CNT/polymer foams at comparable EMI SE level. The addition of PI endows the CNT/PI foam with excellent heat resistance. The as-prepared CNT/PI foam presents higher EMI SE than 35 dB even after being subjected to the flame of alcohol burner. Moreover, the CNT/PI foam exhibits high compressive strength and modulus of 240.9 and 323.9 KPa. These results indicate the potential application of the CNT/PI foam as a high-efficient and lightweight EMI shielding material in the fields of aerospace, automotive, and electronic devices.