There is disadvantage on tofu production by using stove for boiling the soymilk, that is decrease tofu quality especially on the aroma. One of the way for avoiding such problem is by utilizing steam system on tofu production processing. For producing the steam, some tofu industries utilize used-drum of oil. Low safety factor, high on energy losses, and take a long time on steam production are the problems from using the drum. Therefore, it is imperative to design and develop mini boiler in order to solve such problems. The mini boiler design was planned with fire tube system and using gas as the fuel. There are several steps for designing and developing mini boiler. The objective of this study was to do preliminary analysis, that is to obtain steam parameters requirement (energy, capacity, temperature, and pressure) for boiling the soymilk which is the first step of development design the mini boiler. Analytical method was used. The steam parameters requirement were obtained and ready to be used for the n...