The invention discloses a quartz wafer detergent and a preparation method thereof and belongs to the technical field of detergents, aiming to solve the problems that an existing quartz wafer detergent has chemical residues and is incapable of cleaning quartz wafers thoroughly.The quartz wafer detergent is prepared from, by weight, 6-10 parts of coconut oil, 9-15 parts of citrus juice, 16-22 parts of maize oil, 2-7 parts of sodium chloride and 48-68 parts of purified water.The preparation method includes weighing the raw materials according to the parts by weight, adding the purified water, sequentially adding the coconut oil, the citrus juice, the maize oil and the sodium chloride into a reaction kettle with a stirring function, stirring for 50-90 minutes by controlling the temperature of the reaction kettle between 20 DEG C and 32 DEG C, inspecting whether a mixture is qualified or not after uniform stirring, metering and filing so as to obtain the quartz wafer detergent.The quartz wafer detergent is reasonable and feasible in formula, facilitates cleaning and is applicable to cleaning of the quartz wafers such as SC-cut quartz wafers, SMD (surface mounted devices) quartz wafers and 49S quartz wafers.