「正劇」是戲劇學重要概念之一，但中國大陸學界對其界定充滿歧義。本文通過辭源考證發現，作為戲劇體裁之一的「正劇」在1949年以前並不存在。它是中國共產黨建立新政權後，蘇聯專家來華指導戲劇實踐的產物。孫維世最早將俄語詞драма翻譯為「正劇」，並通過中央戲劇學院的「導演幹部訓練班」將這一概念傳播給戲劇界。在當時，它特指為工農兵服務的社會主義現實主義作品。戲劇理論家陳瘦竹將「正劇」觀念追溯到狄德羅，為這個概念提供了更豐富的內容。「正劇」（drama）觀念在現當代中國大陸的接受與展開，是一個具有豐富文化內涵的事件。從中國現代戲劇的發展史看，追求「啟蒙」的「新劇」是對狄德羅戲劇觀念的繼承；而「啟蒙」之變奏所催生的「正劇」則是馬克思主義戲劇觀影響下的產物。兩者在文體形式、美學原則和思想價值上體現出鮮明的共性與差異。

“Zhengju” is one of the important concepts in theatre research, but its definition is full of ambiguity in Chinese academic circle. Through the research of its etymology, this article finds that “Zhengju,” as one of the genres of drama, was not a concept existing by 1949. It was the product of Soviet experts coming to China to guide the practice of Chinese theatre after the founding of the People’s Republic of China. Sun Weishi first used the Chinese word “Zhengju” to translate the Russian term “драма,” and through the “director cadre training class” hold by the Central Academy of Drama, the concept soon was spread to the public. However, at that time, the term specifically referred to socialist realistic works for workers, peasants and soldiers. Drama theorist Chen Shouzhu traced the concept of “Zhengju” back to Diderot (1713-1784) by providing more understanding for the concept. The acceptance and development of the concept of “Zhengju” in modern and contemporary China is with rich cultural connotation. According to the history of Chinese modern theatre, “Xinju” which pursued enlightenment was the inheritance of Denis Diderot’s concept of “drame,” while "zhengju," impacted by the transformation of "enlightenment," is the product of Marxism. They have similarities and differences in stylistic forms, aesthetic principles and ideological values.