A heat pipe type adsorption ice maker with two adsorbers for fishing boats is designed by using ammonia as refrigerant and compound of activated carbon-CaCl2 as adsorbent. This type of heat pipe adsorber can solve the problem of incompatibility between ammonia, copper, seawater and steel. The working process of the ice maker with 8.7 kg adsorbent per bed is simulated. The results show that the optimal semi-cycle time is about 9 min at the evaporating temperature of -15 degrees C, where the corresponding cooling power, specific cooling power per kilogram adsorbent SCP and coefficient of refrigerant performance CCP are respectively 3.6 kW, 217 W center dot kg(-1) and 0.404.