An encased syringe in which a prefilled syringe is accommodated in a case , wherein the prefilled syringe includes a cylindrical syringe body filled with a foamable material ; a nozzle provided at an end of the syringe body ; and a plunger pressed into the syringe body on one end side, the case includes a syringe accommodating part that includes a body accommodating part formed to be depressed along a shape of the syringe body to accommodate the syringe body ; a nozzle accommodating part formed to be depressed along a shape of the nozzle to accommodate the nozzle , the nozzle accommodating part being different in depth from the body accommodating part ; and a plunger accommodating part formed to be depressed along a shape of the plunger to accommodate the plunger , wherein the length (Lc) of the plunger accommodating part is smaller than the length (Lp) of the plunger in an axial direction of the prefilled syringe , characterized in that the syringe body is locked by a step between the nozzle accommodating part and the body accommodating part that are different in depth, wherein said difference in depth defines said step so that a displacement of the prefilled syringe accommodated in the syringe accommodating part toward a side of the nozzle in an axial direction of the prefilled syringe accommodated in the syringe accommodating part is restricted. the prefilled syringe includes a cylindrical syringe body filled with a foamable material ; a nozzle provided at an end of the syringe body ; and a plunger pressed into the syringe body on one end side, a cylindrical syringe body filled with a foamable material ; a nozzle provided at an end of the syringe body ; and a plunger pressed into the syringe body on one end side, the case includes a syringe accommodating part that includes a body accommodating part formed to be depressed along a shape of the syringe body to accommodate the syringe body ; a nozzle accommodating part formed to be depressed along a shape of the nozzle to accommodate the nozzle , the nozzle accommodating part being different in depth from the body accommodating part ; and a plunger accommodating part formed to be depressed along a shape of the plunger to accommodate the plunger , wherein the length (Lc) of the plunger accommodating part is smaller than the length (Lp) of the plunger in an axial direction of the prefilled syringe , a body accommodating part formed to be depressed along a shape of the syringe body to accommodate the syringe body ; a nozzle accommodating part formed to be depressed along a shape of the nozzle to accommodate the nozzle , the nozzle accommodating part being different in depth from the body accommodating part ; and a plunger accommodating part formed to be depressed along a shape of the plunger to accommodate the plunger , characterized in that the syringe body is locked by a step between the nozzle accommodating part and the body accommodating part that are different in depth, wherein said difference in depth defines said step so that a displacement of the prefilled syringe accommodated in the syringe accommodating part toward a side of the nozzle in an axial direction of the prefilled syringe accommodated in the syringe accommodating part is restricted. <EOS>