The rapid development of the shipping industry has led to a significant increase in exhaust emissions from ships. Ship plume emissions are characterized by wide distribution and high mobility. These emissions are often hidden, uneven, and highly variable, making their regulation extremely challenging. In response to this, the present study designed and developed a high-precision, high spatiotemporal resolution UV imaging remote sensing system for the real-time, remote monitoring of SO2 emissions from ship exhausts. The system employs a three-channel design, utilizing dual-wavelength channels at 310 nm and 330 nm to eliminate interference and accurately capture SO2 signals, with a spectral channel used for cross-verification of accuracy. The monitoring system integrates the 2-IM sky background reconstruction method, a self-calibration technique, and an optical dilution effect correction algorithm, enabling the precise acquisition of optical thickness images and real-time inversion of SO2 concentrations. Additionally, through an emission rate inversion algorithm, the 2D SO2 concentration data are converted into intuitive emission rate information, further enhancing the practicality and interpretability of the monitoring data. Experimental results show that the self-calibration technique can fit calibration curves in real time with an error of only 2.35%. After optical dilution correction, the camera’s detection limit reaches 3.84 ppm·m at 623 m, and it still maintains a high sensitivity of 6.24 ppm·m at 1 932 m. These results fully demonstrate that the system meets the performance requirements for monitoring distant, low-concentration, mobile pollution sources. The development of this system not only provides robust technical support for the monitoring and control of marine pollutants but also aids in understanding the characteristics of ship emissions and the diffusion mechanisms of gaseous pollutants.