Metal-organic frameworks (MOFs) are based on metals and organic linkers; they possess large surface areas, suitable pore size and shape, wide range of chemical composition, and functionalized pore surface, which enable them for possible applications as delivery vehicles for therapeutic agents. The challenges include not only the development of new solids but also continuous improvements in the formulation and processing of the materials, including modifying the morphology and shape of the frameworks to fit the proposed applications of drug delivery. This chapter discussed enormous MOF-based stimuli responsive drug delivery systems, and considerable achievements have been made as a new avenue for drug delivery, their structural aspects, their applications in the controlled release of the drugs, and future view for development of drug controlled release researches using MOFs. Among the properties that must be developed and approved are the materials' toxicology, stability, their reproducibility of manufacture of MOFs in body's liquid, and pharmacokinetics of drug-loaded MOFs.