臺灣道路與日本道路同具「後進性」，迨至1920年代後期總督府改變交通政策，決策擱置環島鐵路計畫，代之以汽車運輸來完成環島交通，才積極推動道路改良事業。經費龐大的國庫事業大增，修築縱貫道路和連絡臺灣東西部的幹線道路；地方事業則是在1930年制定「道路費國庫補助規程」和「道路構造規程」後，推動國庫補助道路改修計畫及追加計畫；各州、廳獨自推動的道路橋樑改修事業，主要是配合幹線道路改良事業的相關維護、修繕。 1930年前後，隨著新觀念「鋪設是一項投資」的普及和汽車運輸之需求，各州及島內重要都市先後提出鋪設計畫，自日本引進合適的鋪面，或由各州廳自行研發，近代鋪設道路進入積極拓展期。總之，進入改良時期後，在國庫支持與民力動員下推動各項計畫，道路在質、量上均大幅提升。然而，相較同時期日本，臺灣道路不論是單位面積之里程、與人口之相對密度、道路鋪設率，皆落後甚多。然而，此一時期的道路改良事業使臺灣道路邁向近代化，配合蓬勃發展的汽車運輸業之需求，為總督府的鐵路、港灣、汽車運輸之交通整合政策奠定初步的基礎。

Taiwan's road system, like that in Japan, was rather "backward." During the late 1920s, the roads construction in Taiwan began to make substantial progress after the Palace of Governor-General declaring a new policy on road system. The Palace decided to shelve the plan of constructing the round-island railroad and replaced it by the round-island roads for motor transportation. The government increased its budge to construct the road to connect the south and the north, the east-west trunk road, constructing a complete network of road in Taiwan. As to the construction of regional roads, it started after enacting "The Regulation of the Treasury's Subsides to Road Construction" and "The Regulation on Road Construction" in 1930. Under these two regulations it was made clear that the construction of country roads and bridges should be initiated by each county or district in accordance with the maintenance and repair of the main lines. Before and after 1930, with the new idea that road construction is a kind of investment and the increasing demands for motor vehicles, many counties and cities on the island aggressively submitted plans on the construction of roads, those plans are following the Japanese patterns or creating new forms for themselves. In this highly active period of road construction, many roads were built with very good quality under the help of the national treasury and the general public. However, compared to the roads construction in Japan, the roads of Taiwan then were far too few in proportion to the population. In short, the development of the road construction in Taiwan was initiated by the Japanese colonial government, it definitely contributed to the road transportation.