Underwater prepacked aggregate concrete is generally used in construction of dock floor of large dock，water stopping works for dock walls and cofferdams for docks being built in wet, counterweight blocks in dock floors，improvement of foundation beds for gravity caissons，reinforcing rock-fill in caissons for heavy-duty wharfs and leakage stopping works in docks. Based on the summary and analysis of the actual results of related projects，the paper discusses the properties of under-water prepacked aggregate concrete and the problems to attend to during the construction，with a view to provide refer nce for the determination of design parameters, construction process control，quality acceptance standard for similar projects.