The invention provides a string and a method for quickly surveying water in horizontal well by multi-parameter combined test without moving the string. Mainly, test instruments (such as a flow meter and a pressure meter) are conveyed to the bottom of the well by means of an oil tube, the test instruments are connected with the oil tube in a threaded manner and are tripped in a horizontal segment of the horizontal well along with packers. According to a number of fracturing modified segments of the horizontal well and water breakthrough features, under supporting of different amounts of packers, the horizontal segment is packed into different production intervals; each production zone segment is provided with the corresponding flow meter, pressure meter and the like. After the test string is tripped in the well, the well is shut for pressure recovery test of each interval, the well is opened for production after pressure recovery test is finished, production and drainage are performed with a high-capacity drainage parameter, the string is tripped out after a certain period of production time, changes in parameters such as pressure meter pressure, temperature and flow are played back, parameters of the jammed intervals are tested interval by interval, and a water production interval is comprehensively determined; water surveying accuracy and efficiency of the horizontal well are improved.