With the introduction of the purposes of strata improvement for EPB TBM driving at its start and arrival, and the presentation of calculation method and design situation of strata improvement, the authors discuss the problems in calculation method and design situation for strata improvement in detail. Furthermore, they analyse the reasonable strata improvement scopes at the start and arrival of EPB TBM in various strata, and put forward their standpoint on strata improvement scopes determination. The strata improvement scope for EPB TBM driving at its start and arrival should be determinated in accordance with the strata situation, length of shield machine and strength and stability of ground. This paper gives a further definition of the purposes, effects and significance of strata improvement and can provide references for reasonable strata improvement scopes for shield driving at its start and arrival in different strata.