As an emerging and growing family of two-dimensional transition metal carbides, carbonitrides, and nitrides, MXenes have received increasingly close attention due to their intriguing surface features, excellent electrical conductivity, and layered structures. The spatial conditions ascribed by the nanostructure of MXene-based photocatalysts are the decisive factor for their surface and interface characteristics, which play a vital role in expanding the light response range and inhibiting the recombination of photoinduced carriers. Although some reviews focus on the properties, synthesis strategies, and applications of MXene-based photocatalysts, there is still a lack of a comprehensive review that can provide the basis for MXene-based photocatalysts from the perspective of spatial conditions created by various nanostructures. In this review, we systemically summarize the action principles of surfaces and interfaces in MXene-based photocatalysts and highlight the impact of spatial conditions on surface and interface engineering by analyzing recent research on MXene-based photocatalysts. Furthermore, we put forward the advantages and challenges of the research direction of MXenes and MXene-based photocatalysts in the future.