This study aimed to explore the soil salinity and nutrient characteristics of different densities of Tamarix chinensis on the beaches of the Yellow River Delta, and to clarify the "salt valley" and "fertile island" effects of T. chinensis with different densities. This paper took the low-density (1100 trees/hm²), medium-density (4100 trees/hm²) and high-density (7100 trees/hm²) T. chinensis near Binzhou Port in Shandong Province as the research object. Soil pH, electrical conductivity, available nitrogen, available phosphorus, available potassium and other indicators of T. chinensis of different densities and different locations around the plants were measured and analyzed. The results showed that:(1) the soil electrical conductivity gradually decreased with the increase of density. In medium and high density T. chinensis forests, the soil electrical conductivity was reduced by 28.39% and 55.74% respectively compared with low density; Varying with the distance from the T. chinensis, the soil electrical conductivity of medium and high density T. chinensis showed the root < canopy center < canopy brim < interspaces. That is, the "salt valley" effect appeared in the medium and high density T. chinensis, but the low-density T. chinensis effect did not appear. (2) The contents of soil available nitrogen, available phosphorus and soil organic carbon first increased and then decreased with the increase of forest density. In medium and high density T. chinensis, there were significant differences in the contents of available nitrogen, available phosphorus and soil organic carbon at different positions of the T. chinensis (P<0.05), which was expressed as root < canopy center < canopy brim < interspaces, while there was no significant difference in low-density T. chinensis (P>0.05). The medium and high density T. chinensis had a "fertile island" effect, but the low-density T. chinensis did not appear. (3) Medium-density T. chinensis was higher than high-density in terms of nutrient content and nutrient enrichment rate, and lower than high-density in terms of salt enrichment rate. It had stronger "fertile island" and "salt valley" effects. (4) There was no significant difference in soil pH between different densities of T. chinensis and different positions around the plants (P>0.05). Forest density significantly affected soil salinity and nutrient content. Medium-density T. chinensis had a better effect on improving soil fertility, followed by high-density, and low-density was worse. The salt reduction effect of T. chinensis with different densities was better in medium and high densities, and worse in low densities. Based on the effect of T. chinensis on improving soil salinity and nutrients, it is suggested that the reasonable initial planting density of T. chinensis on the beaches of the Yellow River Delta was 4100 trees/hm².