Superconducting quantum interference device (SQUID) is one of the most sensitive flux sensors and is critical in fields such as biomagnetism, low-field nuclear magnetic resonance (NMR), and geophysics. In this paper, an integrated magnetoencephalography (MEG) SQUID chip is investigated in detail, which consists of a magnetometer and two gradiometers. The SQUID and pick-up coils are fabricated on different-sized wafers. The SQUID is fabricated on a commercial silicon substrate using micro- and nano-fabrication processes, including thin-film growth, i-line stepper photolithography, and reactive ion etching (RIE). The sub-micron Josephson junction technology is employed to achieve a junction size of 0.7 μm×0.7 μm with a junction capacitance of only 0.05 pF. The pick-up coil is designed as a single-turn coil for a magnetometer and a planar first-order gradient coil for a gradient sensor. The MEG SQUID chips are tested in a well-shielded chamber with the helium-liquid temperature (4.2 K). Customized low-voltage noise readout circuit and source measure units are used to characterize the magnetic field white noise, current-voltage (I-V) characteristics, and voltage modulation amplitude of 171 SQUID channels. The results show that 81% of the SQUID chips exhibit the lower magnetic field noise (< 5 $ {\text{fT/}}\sqrt {{\text{HZ}}} $), and the high modulation amplitudes (in a range of 80–120 μV) with the low working currents of 15–20 μA, yielding a wafer yield rate of 78%. In summary, the SQUIDs show excellent performance in terms of magnetic field white noises, modulation amplitudes, and working currents, which are suitable for the very weak magnetic signal detection. One of future studies will focus on optimizing the SQUID chip fabrication process to minimize performance variations between chips on the same wafer.