JIT-oriented parts distribution processes have some particular characteristics，such as abundant SKUs，small batches and dispersed in-out warehouse time．It is very challenging to optimize the storage loca_x005ftion assignment in the distribution center． This paper models the storage location assignment problem with time dimension as a special triangle packing problem，and develops a heuristic for solving it．Numerical study with the real case shows that the proposed model and heuristic method are very useful in practice; they can reduce the operating cost and improve the spatial utilization significantly．