Wound postoperative infection and adhesion are prevalent clinical conditions resulting from surgical trauma. However, integrating intraoperative repair and postoperative management into a dressing suitable for wounds with unpredictable surface shapes and surroundings remains a formidable challenge. Here, we attempt to introduce a dynamic antifouling surface as wound protective covering and report an in situ formation of slippery-adhesive Janus gel (SAJG) by assembling hydrogel (N-hydrosuccinimide ester-activated powders) and elastomer (Silicon oil-infused polydimethylsiloxane). First powders can rapidly absorb interfacial water to gel and bond to tissue based on network entanglement, forming a tough adhesive hydrogel. Then precured organosilicon is applied to hydrogel and bonded together, forming a slippery elastomer. Due to the molecular polarity difference between hydrogel and elastomer, SAJG exhibits anisotropic surface behavior as evidenced by liquid repellency (hydrophilic vs. hydrophobic), and adhesion performance (bioadhesion vs. antiadhesion). Further, in vivo models are constructed and results demonstrated that the SAJG can effectively prevent bacterial infection to promote wound healing and avoid postoperative adhesion. Predictably, the morphologically adaptive SAJG with slippery and adhesive properties will have tremendous potential in addressing complex wound infections and postoperative complications.