Marine engine data process equipment is being studied to cope with the rapid development of automation and remote control systems adopted in ships. Developed originally for land use, however, this equipment seems to have various problems yet to be studied with regards to the utility and economy for marine use. Author's study on various types of equipments best meets the required function. As to the surrounding conditions, each factor ; i.e., temperature, humidity, vibration and shock ; measured on board ships was analyzed and approximate standards established from the relations between each of those factors and reliability, life and cost.