The invention relates to a water-based fully-synthetic titanium alloy cutting fluid. The titanium alloy cutting fluid is prepared from components in percentage by weight as follows: 1%-20% of a main lubricating agent, 1%-10% of an auxiliary lubricating agent and the balance of water. The titanium alloy cutting fluid belongs to a water-based fully-synthetic metal machining fluid, doesn't contain oily ingredients such as mineral oil, plant oil and the like, doesn't contain nitrite, secondary amine, formaldehyde, formaldehyde releasing substances, chlorine, chromium or other elements, is friendly to the environment and human bodies, doesn't easily decay and is long in service life.