Plasma merging is a unique method of plasma start-up, and magnetic reconnection is a key process for plasma heating in this method. On the University of Tokyo Spherical Tokamak (UTST), we use a pickup coil array to obtain the macroscopic behavior of magnetic reconnection, but direct measurement of the localized current is still necessary to study the details of the magnetic reconnection process. A small Rogowski coil is a useful tool for measuring small scale currents, and we used five such coils to measure the radial structure near the X-points of merging plasmas on UTST. As a result, we have found current densities up to 1.5MA/m(2), with a typical time scale of several micro seconds. The current density increases with the plasma current, and the average radial width is about 30 mm. (C) 2018 The Japan Society of Plasma Science and Nuclear Fusion Research