Traditional downhole measurement methods, when applied to core drilling, are limited by the blockage of the mud pulse transmission channel by the core barrel. This forces the downhole instrument to be installed behind the core drilling assembly, resulting in a large distance between the instrument and the drill bit. This leads to significant lag in trajectory and operating condition data, hindering precise control of drilling process and trajectory. This paper proposes a near-bit downhole measurement system for wireline core drilling to address this issue. The system utilizes a near-bit transmitting unit to collect operating conditions and trajectory data in real time. The collected data is transmitted via very low frequency electromagnetic waves to a receiving unit connected to the core drilling assembly"s inner tube, where it is stored. After core extraction, the instrument is lifted along with the core barrel for data retrieval. This paper introduces the system"s overall scheme and circuit design. Detailed