Deposition technologies are essential for fabricating paper-based sensors and devices, enabling precise control over material properties and device architecture. This chapter explores various deposition methods, including vapor deposition, electrodeposition, vacuum deposition, and spray coating, highlighting their principles, advantages, and limitations. Given the rising interest in paper-based devices due to their flexibility, biodegradability, and low cost, this chapter discusses material considerations and applications specific to paper substrates. Furthermore, it examines recent advancements in nanotechnology and their impact on deposition techniques for paper-based sensors and devices, emphasizing the importance of optimizing these techniques for improved device performance and broader applicability.