The invention discloses a high/low temperature water cycle injection molding process for an outer frame of a high gloss flat panel television, which comprises the following steps: 1) softening tap water via a water softening device at first; 2) pressurizing the softened water to the pressure between 0.9 and 1.0Mpa via a high pressure water pump, and heating the softened water to the temperature from 150 to 180 DEG C by using an electric heating rod so as to realize non-vaporization; 3) feeding hot water into a stationary mold of an injection mold via the high pressure water pump and the control of a valve to uniformly heat the stationary mold to the temperature from 110 to 120 DEG C, and then implementing injection molding by adopting ABS/PMMA plastic alloy; 4) withdrawing the hot water in water passages back to a container upon the completion of glue injection, feeding in cold water to cool the mold to the temperature below 50-60 DEG C, and opening the mold and taking out the workpiece after about 15-30 seconds of the cooling. According to the invention, high temperature high pressure cold/hot water cycle injection process is adopted to effectively eliminate dissolution mark on the frame of the flat panel television, enhance the gloss on the surface of the product and achieve spraying-free effect, therefore, the process can be extensively applied to the production of the outer frame of the high gloss flat panel television.