The integration of carbon nanotubes (CNTs) into polymer matrices has led to the development of advanced composites with exceptional mechanical, electrical, and thermal properties, particularly suitable for 3D and 4D printing applications. This paper explores the synthesis, properties, and potential applications of carbon nanotube-reinforced 3D and 4D printable conductive polymer composites. CNTs, known for their high tensile strength, conductivity, and aspect ratio, enhance the performance of polymer composites, making them ideal for creating lightweight, strong, and conductive materials. The dispersion and alignment of CNTs within the polymer matrix are critical challenges addressed through advanced techniques such as in-situ polymerization, ultrasonication, and surface functionalization. Additionally, the scalability and cost of producing these composites are examined, highlighting recent advancements aimed at more economical production methods. Environmental and health implications are also considered, ensuring safe usage and disposal of CNT-infused materials. Innovations in 4D printing, which involve materials that can change shape or properties in response to external stimuli, are discussed, showcasing the expanding capabilities and applications of these composites in fields like aerospace, biomedical devices, and soft robotics. The ongoing research and technological advancements underscore the transformative potential of CNT-reinforced 3D and 4D printable conductive polymer composites in various industrial and technological domains.