Multi-Objective Genetic Algorithm (MOGA) is successfully applied to design
and optimize the Advanced Ligh Souce (ALS) storage ring lattice for its
future upgrade. In stead of the conventionally used dynamic aperture area,
the total diffusion rate is used as an objective to optimize the dynamic
aperture of the lattice, which leads to a superior performance in nonlinear
beam dynamics.  To find a best overall working lattice, we explore
optimizing the linear and non-linear properties of lattice simultaneously
using MOGA. Compared to the widely used Dynamic Aperture Tune Scan (DATS)
technique, MOGA not only allows us to rapidly find a best working point in
a wide searching range, but also provides us trade-offs among the
optimization objectives, such as the low emittance, small beta function and
large dynamic aperture. These trade-offs give us a guideline to choose a
candidate lattice for ALS future upgrades.