Kappa sounding rockets instrumented to measure the magneitc field with Sq current system were flown to altitude near 200 km over Kagoshima Space Center of Tokyo University, Uchinoura. Rubidium-vapor magnetometer were used to detect low-latitude ionospheric current. The first measurements of ionospheric current in Japan ware made with flux-gate magnetometer in Kappa 9M-7 rockets. The results obtained suggest the existence of a current sheet with lower edge at 105 km. Moreover, in this paper, it will be discussed the ionospheric current systems as deduced from ground observations.