Solar-driven interfacial evaporation is widely considered a promising low-cost and sustainable technology for desalination; yet, persistent salt fouling on photothermal layers severely limits its long-term stability under high-salinity conditions. Contactless evaporation provides an alternative strategy by physically separating the photothermal absorber from saline water with an air gap, where longwave infrared radiation serves as the dominant heat transfer pathway to drive interfacial evaporation. This design fundamentally prevents direct salt deposition on photothermal components and offers a promising route toward stable solar desalination in harsh brine environments. Although contactless evaporation has developed rapidly since its introduction in 2018, it has rarely been reviewed as an independent research field. This review presents a focused overview of contactless evaporation for solar desalination. The coupled transport mechanisms of radiative, conductive, and convective heat transfer, together with vapor diffusion across the air gap, are first summarized. Then, modeling approaches ranging from one-dimensional thermal resistance networks to two- and three-dimensional finite-element multiphysics simulations are outlined. Recent advances are then categorized into three major directions: spectrally matched absorber-emitter materials, geometric optimization of parallel and non-parallel architectures to balance radiative coupling and vapor transport, and hybrid systems integrating contactless and conventional interfacial evaporation for heat loss suppression and residual heat recovery. Representative devices are further compared in terms of evaporation performance, anti-scaling durability, scalability, and economic potential. Finally, key challenges are identified, including insufficient multiphysics modeling under realistic conditions, limited spectral co-design of materials, structural trade-offs between heat delivery and vapor escape, and the lack of standardized desalination-oriented evaluation metrics. Future efforts should focus on unified high-fidelity modeling, spectral engineering, integrated geometric and heat-recovery design, and standardized performance reporting.