This study investigates the superhydrophobicity, antibacterial activity, and electromagnetic interference (EMI) shielding properties of cotton fabrics coated with Ag/PDMS. The effects of varying concentrations of silver nanoparticles (Ag NPs) and polydimethylsiloxane (PDMS) on these functionalities were examined. The results show that the surface roughness of the coated fibers significantly influences their superhydrophobicity, with the highest superhydrophobicity observed in fabrics coated with 2 g/L Ag NPs and 20 g/L PDMS. The antibacterial activity against *Escherichia coli* and *Staphylococcus aureus* was found to be highly dependent on the concentration of Ag NPs, with the highest efficacy at 4 g/L. The EMI shielding performance was enhanced by increasing the concentrations of Ag NPs and PDMS, with a reflection coefficient (R) increase of over 500% compared to untreated fabrics. The superhydrophobicity remained durable after 1000 abrasion cycles, and the antibacterial activity persisted even after multiple washes. The study highlights the importance of Ag NPs and PDMS in developing multifunctional cotton fabrics for practical applications in antibacterial, superhydrophobic, and EMI shielding fields.This study investigates the superhydrophobicity, antibacterial activity, and electromagnetic interference (EMI) shielding properties of cotton fabrics coated with Ag/PDMS. The effects of varying concentrations of silver nanoparticles (Ag NPs) and polydimethylsiloxane (PDMS) on these functionalities were examined. The results show that the surface roughness of the coated fibers significantly influences their superhydrophobicity, with the highest superhydrophobicity observed in fabrics coated with 2 g/L Ag NPs and 20 g/L PDMS. The antibacterial activity against *Escherichia coli* and *Staphylococcus aureus* was found to be highly dependent on the concentration of Ag NPs, with the highest efficacy at 4 g/L. The EMI shielding performance was enhanced by increasing the concentrations of Ag NPs and PDMS, with a reflection coefficient (R) increase of over 500% compared to untreated fabrics. The superhydrophobicity remained durable after 1000 abrasion cycles, and the antibacterial activity persisted even after multiple washes. The study highlights the importance of Ag NPs and PDMS in developing multifunctional cotton fabrics for practical applications in antibacterial, superhydrophobic, and EMI shielding fields.