The significance of object-oriented programming (OOP) in software design lies in its focus on the organization of code into reusable and manageable components called objects. OOP principles such as encapsulation, inheritance, and polymorphism enhance code maintainability, scalability, and flexibility. This paradigm facilitates collaboration among developers, as objects can be designed, tested, and modified independently. By mirroring real-world entities, OOP improves the alignment between software design and business requirements, leading to higher efficiency in development and a better ability to adapt to changes.