The invention discloses a low direct current clamp-shaped measuring device, which belongs to the technical field of electrotechnics, solves the problems of low sensitivity and precision when the existing current sensing device is used for measuring industrial tiny direct current, and is used for accurate measurement in the field of low direct current industry with reliable and stable operating structure. The measuring device comprises a sensor head, a modulation transformer, a band-pass filter, a phase sensitive demodulator, a direct current amplifier and a power amplifier, wherein the sensor head is annular, and comprises a first half ring detection core and a second half ring detection core in an upper half ring U-shaped detection core as well as a third half ring detection core and a fourth half ring detection core in a lower half ring U-shaped detection core. After the upper and lower half ring U-shaped detection cores are assembled, the overall magnetic shielding core is placed in an annular half cavity formed by shielding layers on two sides, and a feedback winding is wound outside the annular magnetic shielding core. The measuring device can realize accurate measurement of industrial tiny direct current; and the sensor head has a clamp-shaped structure, so that the measuring device is high in measurement sensitivity and accuracy and is suitable for industrial application.