本研究探討至美國第二上市(ADR)企業之財務報導品質是否會因為受更嚴謹的法規管制所影響。為了排除不可控制的國家背景既定影響，選擇投資環境與美國同樣具高投資者保護的英國(已開發國家)及台灣(開發中國家)為樣本。研究結果顯示英國有ADR之企業相較於沒有ADR之企業在跨國上市前，較不會從事盈餘管理。而台灣有ADR之企業於跨國上市後持續改善財務報表品質，因此相較於跨國上市前，較不會從事盈餘管理。而英國有ADR之企業在跨國上市後相較於跨國上市前，並沒有顯著差異。此結果顯示當開發中國家之企業受到另一嚴格的監理機關所監督時，較不會從事盈餘管理。在跨國上市後與美國企業及沒有ADR企業之比較結果顯示，英國ADR企業相較於美國企業及沒有ADR之企業有較高的盈餘波動。而台灣ADR企業相較於美國企業及沒有ADR之企業有較平穩之盈餘。以上結果顯示雖然ADR企業都受到美國監理機關監督，但其財務報表品質還是會受到本國環境影響，因此英國ADR企業及台灣ADR企業在跨國上市後相較於美國企業卻有不同之財務報表品質。 This paper examines how cross-listing in highly developed markets with stringent securities laws shape firms’ incentives to report earnings which reflect a firm’s underlying performance. By selecting firms from countries of U.K.(developed) and Taiwan(emerging), with strong investor protection, this study results that UK cross-listed firms show relatively less evidence of earnings management comparing to non-cross-listed firm in the pre-listing period. Taiwan cross-listed firms continuously improve their reporting system by showing lesser evidence of manipulating earnings in the analysis between pre and post-listing period. However, UK CL firms’ behaviour of reporting earnings in the post-listing period remains unchanged in the comparison with pre-listing period. This suggests that firms come from a less developed market will engage less in earnings smoothing when they are under the supervision of two authorities and in compliance with two sets of stringent rules. In the comparison among U.S. matched firms and non-cross-listed matched firms, cross-listed UK firms’ have less smoothed income than other two types of firms in the post-listing period. Meanwhile, cross-listed Taiwan firms show a more smoothed income than US and non-cross-listed firms. Altogether, the result evidences that firms’ earnings management behaviour are still prone to the market which firms operate in, and result in the cross-listed U.K. firms yield a reporting quality that’s comparable to U.S. matched firms while cross-listed Taiwan firms do not.