[Background] Chain pin method is applied widely in monitoring soil and water loss. The traditional chain pin method is insufficient when it is used in complex terrain. Without special measuring device, the monitoring error would be generated, thus the traditional measuring device should be improved. [Methods] According to the topography and cultural relics distribution of the Longevity Hill in the Summer Palace, improved chain pin method was deployed and the pins were produced with stainless steel. After geological exploration and topographic feature survey, hundreds of pins were embedded at 18 sites where there may be serious soil and water loss and be shady for tourists. To reduce the measurement error, a special measuring device was invented. The new device can measure soil and water loss data of measuring pin and more than one points around pin. [Results] Analyzing measured data using the new single-pin multiple-point device, the following results were obtained. 1) Several influencing factors such as soil, slope and vegetation were considered in these 18 sites, which fully reflected the soil and water loss conditions of the Longevity Hill. 2) By the new measuring device, the subjective and objective errors from the environmental conditions and reading data were efficiently reduced, consequently the accuracy of monitoring the soil and water loss by the method of chain pin increased. Measuring accuracy of traditional method was 5 mm, and the measuring accuracy from new single-pin multiple-point device was 1 mm. 3) Principle of statistics was used to processing data, and the result from analyzing the monitored data showed that during the period of monitoring, value of water and soil loss on the Longevity Hill was in range of -3 mm to +1 mm. [Conclusions] The new single-pin multiple-point device of monitoring the soil and water loss was applied successfully on the Longevity Hill in the Summer Palace. The new device is practicable in monitoring soil and water loss and it can improve the precision. During the period of 3 years of monitoring, the value of water and soil loss on the Longevity Hill was in range of -3 mm to +1 mm.