Junction field-effect transistor has a large input impedance and low noise, which has been widely used to design high performance transient electromagnetic sensor preamplifier circuit. However, the parameters fluctuate greatly between JFET devices of the same type, which makes it difficult to match when the JFET devices are differentially amplified. Aiming at this problem, a low-noise JFET differential amplification technique based on multi-discrete current sources is proposed in this paper. Combined with the characteristics of each JFET amplifier branch circuit, the constant current source is designed separately and adjusted to the optimal static operating point to eliminate the problem of uneven current flow and unreliable operation of the amplifier branch caused by the discreteness of JFET parameters. Finally, the LTspice simulation and actual circuit test results show that the differential amplifier circuit designed based on this technology can work reliably, and the current of each JFET branch is 4.68 mA, and the gain of the amplifier circuit designed based on this technology reaches 40.00 dB and the noise floor is 0.51 nV/Hz@1.10 kHz. The new method proposed in this paper can effectively eliminate the discrete problem of JFET parameters, and lay a good technical foundation for designing a differential parallel low-noise TEM sensor preamplifier circuit.