The invention discloses a method and system for diagnosis and elimination of a liquid trapping phenomenon in a regeneration tower system. A regeneration tower in the regeneration tower system is provided with a remote thermometer, a remote pressure difference gauge and a remote liquid level gauge, temperature, pressure level difference and liquid level monitoring values at different times are displayed on a DCS screen, and a curve taking the time as the horizontal axis is further formed; when monitored temperature difference is not smaller than delatT1, and the temperature difference change frequency is not smaller than f; or when monitored liquid level difference is not smaller than delatx, and the liquid level difference change frequency is not smaller than f; or when monitored pressurelevel difference is not smaller than P1, the antifoaming agent is placed at the latest within t1 hours; when monitored temperature difference is not greater than delatT2, and the temperature difference change frequency is not greater than f; or when monitored liquid level difference is smaller than delatx, and the liquid level difference change frequency is not greater than f; or when monitored pressure level difference is not greater than P2, the antifoaming agent is stopped at the latest within t2 hours. The system is advantaged in that the foaming degree is predicted in advance, adjustmentis made in advance, environmental accidents in the regeneration tower are avoided, and stability of operation of a sulfur recovery MDEA solution system is improved.