The current calculation models of ground settlement for tunnel excavation cannot reflect ground settlement of tunnel non-synchronous excavation with double-line. Based on the Peck ground settlement formula and Attewell ground settlement formula, displacement release of excavation place and tunnel non-synchronous excavation with double-line have researched. By means of finding a function to replace the accumulated probability curve, the new control function was beneficial to parameter introduced and improvement of the current ground settlement formula. By introducing the non-synchronous excavation distance and the displacement release coefficient of excavation place, A new calculation model for ground settlement process of tunnels non-synchronous excavation with double-line is proposed. The reliability and practical of the calculation models was verified. Research results were very important to analyze the ground settlement affecting the building foundation and pipe under ground.