Abstract: Inclined double-row piles have been widely applied in slope and foundation pit support projects, showing favorable engineering performance. However, their application in subgrade engineering is seldom reported, and design parameters remains difficult to determine. This study investigates the mechanical behavior of positive-negative battered double-row piles under varying row spacings in multi-layered soil foundations, aiming to identify optimal row spacing for subgrade engineering, which is crucial for disaster prevention and mitigation. Based on the test section of the Huizhou-Zhaoqing Expressway in Guangdong Province, this study conducts numerical simulations using the finite element software ABAQUS. Results show that: (1) The bending moment and its peak in both front and rear battered piles increase with rising load and loading stages. The bending moment along the pile shaft initially increases and then decreases, with the peak positive bending moment occurring in the upper-middle section, making it susceptible to flexural failure. (2) Lateral displacement of both front and rear battered piles along the pile shaft initially increases and then decreases, with the maximum displacement also in the upper-middle section. (3) The bending moment and lateral displacement of rear positive-battered piles increase with larger row spacing, while those of front negative-battered piles decrease with increasing row spacing. (4) Peak bending moment of rear positive-battered piles exceeds those of front negative-battered piles; the sum of peak moments decreases with increasing row spacing, while the difference increases. For engineering practice, it is recommended that row spacing be 2–4 times the pile diameter. While increasing row spacing, the flexural stiffness of rear positive-battered piles should be enhanced to ensure foundation stability.