Throughout its long history from the Achaemenids to the Pahlavi, in addition to the diversity in spatial geometry and clever design, the Persian garden has been a bed to meet the needs of gardeners and builders and has had a variety of functions. Therefore, in addition to providing recreational space, the garden is a response to self-sufficiency, economic, agricultural and spatial considerations adapted to the climate of different regions, so that in addition to the main function, secondary functions and multifaceted landscape functions have been considered by garden builders and owners. Birjand due to its strategic location on the eastern borders of Iran and the importance of local rulers in the Qajar and Pahlavi periods; It has been the bedrock of the formation and evolution of important gardens. The purpose of this study is to find how to integrate different functions in the design system of Birjand historic gardens and a comparative study of multifunctional landscape in the studied gardens. The research method is descriptive-analytical and data collection is library and interview method along with field studies in three historical gardens of Birjand (Rahimaabad, Amirabad and Behlgard). The results show that traditional gardeners in designing Birjand gardens have thought about how to integrate different functions in the design system, with the aim of designing and constructing a multi-purpose space. The multifunctional landscape in the studied gardens follows the pattern of the weighted multifunctional landscape, so in the weighted multifunctional landscape, the ground; It is able to provide more than one function while meeting several different but homogeneous needs. The multi-functional landscape design of historical gardens has resulted in a combination of ornamental and fruitful agricultural gardens. In addition, the main functions of Rahimabad, Behlgard and Amirabad gardens are: reception, production and fluid, respectively. It should also be noted that among the three main models of multifunctional landscape (mosaic, weighted and fundamental) the studied gardens have a multifunctional landscape model of weighted (combination of several homogeneous functions in a single space).