Objectives To identify the causes of accidents and occupational diseases of shellfish divers in the small coves de Coquimbo, Los Vilos, and Tongoy, in the Coquimbo Region, Chile, in the period 2008-2018. Methods A structured survey of 44 questions was applied to determine the causes or factors that influence accidents and occupational diseases of shellfish divers in the region; collecting information, experiences and observations of the protagonists. The double entry table, the X2 and C contingency association statistics were used for the data analysis. Results Of the 52 surveys carried out, 28 shellfish divers have had accidents and occupational diseases (53%). The segment that does not complete basic education concentrates 46% of accidents. It also shows incidence, the depth at which diving is done, the consumption of alcohol and tobacco, the non-use of decompression tables and the lack of training. Conclusions The type of accident or associated occupational disease with the highest incidence is decompression syndrome and suffocation, both of which have a high association with alcohol consumption and non-use of decompression tables.