The invention discloses a unidirectional suspension rubbervibration isolator for a single cylinder diesel engine. The unidirectional suspension rubber vibration isolator comprises an upper cover, a base, oilless bearings and a rubber damping element. The upper ends of the oilless bearings are fixedly connected to the bottom of the upper cover. The base is a shell body with a U-shaped groove. The U-shaped groove is internally provided with an inner sleeve, and the oilless bearings extend into the U-shaped groove of the base and form a nest structure with the base. The rubber damping element isarranged in the gap among the upper cover, the oilless bearings and the inner sleeve. According to the vibration isolator, excellent vibration performance of the rubber element is adopted, the rubberelement is sulfurized with the upper cover and the nested sleeve into one, and the functions of vertical decompression and pull are achieved. The unidirectional rubber vibration isolator has high bearing capacity, good fatigue resistance, a simple structure, and is convenient to manufacture, install and maintain.