An object is to provide a breaking strength tester which enables a total inspection of a breaking strength of a honeycomb structure without decreasing production efficiency and enables an accurate detection of a breakage caused by pressurization in the honeycomb structure without requiring complicated work. A breaking strength tester 1 includes: a tubular pressure container 10 having opened both ends to house a part of a pillar-shaped honeycomb structure 100 including a partition walls 104 and a circumferential wall 101; a tubular pressurization elastic body 20 disposed to surround an entire circumference of a pressurized portion having a length equal to or less than 1/2 of a length in an axial direction of the circumferential wall 101 ; a partial pressurization unit which elastically deforms the pressurization elastic body 20 and applies uniform pressure to the entire circumference of the circumferential wall 101 of the pressurized portion of the honeycomb structure 100 housed in the pressure container 10 u
