Provided is a method of manufacturing a high quality phosphonocrotonic acid derivative. The present invention is a method of manufacturing a compound represented by the following Formula (3) by reacting a compound represented by the following Formula (1) with a compound represented by the following Formula (2), which comprises a treatment process using an acid or base. [in the formula, R 1 represents a C 1-6 linear or branched alkyl group that may be substituted by a C 6-10 aryl group, a C 2-6 linear or branched alkenyl group that may be substituted by a C 6-10 aryl group, a C 2-6 linear or branched alkynyl group that may be substituted by a C 6-10 aryl group, or a C 6-10 aryl group, R 2 represents a hydrogen atom, or a C 1-6 linear or branched alkyl group that may be substituted by a C 6-10 aryl group, R 3 represents a C 1-6 linear or branched alkyl group, a C 6-10 aryl group, or a halogen atom, and X represents a halogen atom, and multiple R 1 s may be the same or different].本發明提供一種高品質之膦醯巴豆酸衍生物之製造方法。本發明係使下述通式(1)所表示之化合物與下述通式(2)所表示之化合物進行反應而製造下述通式(3)所表示之化合物的方法,其特徵在於包括使用酸或鹼之處理步驟。[式中,R1表示可經碳數6~10之芳基取代之碳數1~6之直鏈或分支鏈之烷基、可經碳數6~10之芳基取代之碳數2~6之直鏈或分支鏈之烯基、可經碳數6~10之芳基取代之碳數2~6之直鏈或分支鏈之炔基、或者碳數6~10之芳基;R2表示氫原子、或可經碳數6~10之芳基取代之碳數1~6之直鏈或分支鏈之烷基;R3表示碳數1~6之直鏈或分支鏈之烷基、碳數6~10之芳基、或鹵素原子;X表示鹵素原子;複數個R1可相同亦可不同。]
