The study dealt with Nyadran, a tradition that developed among the people of Indonesia, especially Javanese. Nyadran is also enacted by the fishing communities of Desa Bluru Kidul (Bluru Kidul village), Kecamatan Sidoarjo (Sidoarjo district) of Sidoarjo Regency. The main activity of Nyadran is a visit to a shrine located in Dusun Kepetingan of Desa Sawohan, Kecamatan Buduran of Sidoarjo Regency. The purpose of the present study was to describe and analyze Nyadran, the meanings of the cultural activities of Nyadran as perceived by the fishing communities and the reasons why the fishing communities of Desa Bluru Kidul, Kecamatan Sidoarjo of Sidoarjo regency engaged in Nyadran. The present study made use of the qualitative approach and the Grounded Theory developed by Strauss and Corbin as the analytical tool. It employed the Theory of Culture as the main theory and the relevant social theories such as symbolic interactionism, social action and phenomenology to delve into the subject matter. Results showed that Nyadran acted upon by the fishing communities was basically nyekar (a visit) to the shrine of Dewi Sekardadu. The Nyadran tradition as perceived by those who carried it out constituted a form of gratitude to God the Almighty for sustenance they earn. The selametan (a thanksgiving meal) in the shrine of Dewi Sekardadu was based on the belief that the visit to the shrine would bring blessings. The fishing communities continued to engage in the Nyadran tradition since it was considered a good cultural heritage of the ancestors.