A positioning detection device includes a first obtaining circuit to obtain a satellite signal, a second obtaining circuit to obtain a detection signal of an inertial device, a third obtaining circuit to obtain a traveling state of the vehicle body including straight-traveling and turning of the vehicle body, a first calculator to calculate first positioning information in a satellite navigation system to which the satellite signal is applied, a second calculator to calculate second positioning information in an inertial navigation system to which the detection signal is applied, a third calculator to calculate third positioning information in a hybrid navigation system to which the first positioning information and the second positioning information are applied, and an output circuit to output the third positioning information upon obtaining the straight-traveling and to output the first positioning information and/or the second positioning information upon obtaining the turning.