The invention discloses a vibration isolating support structure of a damping spring floating track bed and an installation method thereof, which comprises a pre-buried sleeve (9) and a vibration isolator component (10). The pre-buried sleeve (9) is cast in a floating plate type track bed body (14) as a whole, bearing convex tables (3, 4 and 17) are fixedly arranged in the pre-buried sleeve (9), a pre-buried anchor bar (8) which extends into the bed body is arranged outside of the pre-buried sleeve (9), and the vibration isolator component (10) is arranged in the pre-buried sleeve (9) and can support the floating plate type track bed body (14) and isolate the vibration of the floating plate type track bed body (14) through the pre-buried sleeve (9). The vibration isolating support structure can provide emergency safety measures under the extreme condition, so that when the fatigue fracture of a large quantity of support springs occurs suddenly, the local settlement of the floating plate type track bed can be limited within the safety limit range of a few millimeters, thereby preventing the spring breakage accident to endanger the safe running of trains, and greatly improving the security coefficient of the floating plate type track bed.