「三字集」是左翼知識分子模仿《三字經》的形式，以臺灣話寫成，在1930年前後祕密印製流通的宣傳文書，因為目的在啟迪工農階級意識並宣揚共產主義，不久就遭查禁。藉由「三字集」，本文探討臺灣話文書寫如何實驗性地被運用到工農運動的現場，以為意識形態宣傳與群眾動員的工具。本文關注與鄉土文學運動幾乎同時出現的「三字集」，如何反映臺灣話文書寫在鎔鑄具有現代思維的和製漢語與不斷創造╱改寫新字的過程中，被轉換成為召喚庶民情感與動員底層的力量，並落實言╱文一致的訴求。左翼工農運動雖然在政治行動上失敗了，但「三字集」以舊形式作為新的意識形態載體，化身為革命宣傳與底層煽動的武器，乃1930年代臺灣話文文體實驗與實踐的特殊範例。

Sanziji was a work with a propaganda writing style which emulated that of ancient Chinese three-character style and was widely practiced in writing Taiwanese by Taiwan Red Rescue Association in the 1930s. Sanziji was banned by Japanese colonial government for its connection with communism. By analyzing Sanziji created in the heydays of a literary movement that highlighted countryside, land, and local languages, this paper examines how this Taiwanese writing style as an experimentation for mass mobilization was practiced on the sites of Farmers’ and workers’ movements. This paper investigates the incident of Taiwan Red Rescue Association and the political implications of Sanziji, analyzing the form and content of Sanziji and the regional significance of this three-character style communication. Sanziji embodied a Taiwanese writing which was able to accommodate both Japanese Kanzi and the recently invented terminologies. This writing style, making possible the consistency of literacy/orality, transformed into a mobilizing force that touched people’s hearts in the subaltern class. This paper argues that Sanziji invoked an ancient style to challenge the hierarchy of literacy/orality and turned into an instrument for ideological propaganda and mobilization.