In this work, a highly efficient flame retardant and electromagnetic interference (EMI) shielding coating on cotton fabric was fabricated by a simple solution impregnation and dipcoating method, which involved three layers of polyacetimidate (PEI), ammonium polyphosphate (APP), and Ti3C2Tx. When exposed directly to flame, the PEI/APP coating lead to a char layer resulting in self-extinguishing performance. Particularly, the cotton fabric coated by increasing amounts of Ti3C2Tx gradually achieved EMI shielding performance. When the Ti3C2Tx sheets content was 5.2 mg/cm(2), a high electrical conductivity of 670.3 S.m(-1) and a EMI shielding effectiveness of 31.04 dB were achieved in the X-band with an absorption-dominated mechanism. Besides, such modified cotton fabric also has the potential to be used as an electrical heating material. The temperature could even reach up to about 64.3 degrees C under an applied voltage of just 4 V. Therefore, this work provided a feasible idea for preparing multifunctional fabrics.