A stacked lateral double-diffused metal-oxide-semiconductor field-effect transistor (LDMOS) with enhanced depletion effect by surface substrate is proposed (ST-LDMOS),which is compatible with the traditional CMOS processes.The new stacked structure is characterized by double substrates and surface dielectric trenches (SDT).The drift region is separated by the P-buried layer to form two vertically parallel devices.The doping concentration of the drift region is increased benefiting from the enhanced auxiliary depletion effect of the double substrates,leading to a lower specific on-resistance (Ron,sp).Multiple electric field peaks appear at the cers of the SDT,which improves the lateral electric field distribution and the breakdown voltage (BV).Compared to a conventional LDMOS (C-LDMOS),the BV in the ST-LDMOS increases from 259 V to 459 V,an improvement of 77.22％.The Ron.sp decreases from 39.62 mΩ·cm2 to 23.24 mΩ·cm2 and the Baliga’s figure of merit (FOM) of is 9.07 MW/cm2.