Underwater noise has been measured and assessed in Croatia from the early seventies of the last century. Brodarski institute, in that time the technical institute of the ex Yugoslav Navy, has undertaken measurements of various vessel underwater noise as well as underwater ambient noise mainly on two specific locations of interest. Equipment was acquired, techniques and procedures developed and standardized and knowledge and expertise gathered. The measurements and assessment mainly of the vessel underwater noise were continued throughout the eighties. After two decades of virtual standstill, in the wake of requirements for underwater noise monitoring for Descriptor 11 of EU Marine Strategy Framework Directive (MSFD), a series of pilot underwater noise measurements were carried out. The measurement equipment, techniques and procedures as well as the outline of results are presented. The underwater ambient noise monitoring program for the next period has been established and defined and is also presented in the paper.