The invention discloses an internal strain monitoring device and method for steel pipe concrete. The device is composed of a strain sensing module, a positioning module and a data collection module; the strain sensing module is composed of a test base body, a strain rosette, a lead and a binding post; the positioning module is composed of a positioning pipe, a fixed handle, a movable handle, a torsion spring, a line ranger, an extended positioning rod, a wire rope, a rotating shaft, a spring and a calibrated scale; and the data collection module is composed of a data collector and a computer.The test base body is fixed in a predetermined position by the positioning module, the fixed handle is rotated to adjust the angle of the test base body, and concrete is placed and maintained; and thestrain of the test base body is monitored, and further strain in the predetermined position in the steel pipe concrete is monitored. The test base body is positioned accurately via the positioning module, disturbance of concrete placement to the position of the strain sensing module is eliminated, the problem that a present strain test component tends to offset in a sample is solved, and the device and method can be widely applied to the field of internal strain monitoring and test of concrete.