PROBLEM TO BE SOLVED: To provide a lining material for a denture base which can be produced by an easier operation than a conventional method and in stable quality, and a method for producing the material.SOLUTION: There are provided a photopolymerizable pasty material contains: radical-polymerizable compound; viscosity modifier; photopolymerization initiator; and polymerization accelerator, in which consistency measured according to the regulations of JIS T 6521 is within the range of 20 to 150 mm, and Knoop hardness measured according to the regulations of JIS Z 2251 is within the range of 5 to 100, and a method for producing a lining material for a denture base by using a photopolymerizable pasty material of the present invention, in which the method includes: a step of taking out the photopolymerizable pasty material from the packing material; a step of piling up the photopolymerizable pasty material on a mucous membrane side of a denture; a step of installing the denture into an oral cavity and fitting the shape of the photopolymerizable pasty material to the oral cavity ; and a step of photopolymerizing the photopolymerization pasty material.SELECTED DRAWING: None【課題】従来より簡便な操作で、かつ、安定した品質で製造可能な義歯床用裏装材およびその製造方法を提供する。【解決手段】ラジカル重合性化合物と、粘性調整剤と、光重合開始剤と、重合促進剤とを含み、JIS T 6521の規定に従って測定された稠度が20~150mmの範囲内であり、かつ、JIS Z 2251の規定に従って測定されたヌープ硬度が5~100の範囲内である、光重合性ペースト状物、ならびに、本発明の光重合性ペースト状物を用いて義歯床用の裏装材を製造する方法であって、前記包装材から光重合性ペースト状物を取り出すステップと、義歯の粘膜側に前記光重合性ペースト状物を盛り上げるステップと、義歯を口腔内に装着させ、光重合性ペースト状物の形状を口腔に適合させるステップと、光重合ペースト状物を光重合させるステップとを含む、義歯床用裏装材の製造方法。【選択図】なし