NOVELTY - Reaction device for acclimating sludge and synthesizing polyhydroxyalkanoic ester by sludge comprises a sludge acclimating device and a synthetic reactor.    USE - The reaction device is useful for acclimating sludge and synthesizing polyhydroxyalkanoic ester by sludge (claimed).    ADVANTAGE - The device is suitable for commercial production on large scale and has simple structure, convenient operation, cheap manufacturing cost, and high yield.    DETAILED DESCRIPTION - Reaction device for acclimating sludge and synthesizing polyhydroxyalkanoic ester by sludge comprises a sludge acclimating device and a synthetic reactor, where an acclimating reaction tank and an aeration head are set on the sludge acclimating device; the acclimating reaction tank is set at the bottom of the acclimating reaction tank; gas inlet of the aeration head is connected to a rotator flow meter and an air compressor which set outside the acclimating reaction tank by a connection pipe; the aeration amount of the aeration head is controlled by the rotator flow meter; at least sludge drains for draining sludge are set on wall of the acclimating reaction tank; a constant-temperature water bath tank, a synthetic reaction tank, two microcomputer time controllers, an aeration head and stirrer are set in the synthetic reactor; the synthetic reaction tank is set in the constant-temperature water bath tank; an aeration head of the synthetic reaction and a stirrer are set at the bottom of the synthetic reaction tank; gas inlet of the aeration head is connected to a rotator flow meter and an air compressor which set outside by a connection pipe; and 2 microcomputer time controllers are connected to the stirrer and air compressor in order to control time of aeration and stirring. An INDEPENDENT CLAIM is a method for acclimating sludge and synthesizing polyhydroxyalkanoic ester by sludge comprising: (a) adding the active sludge to the acclimating reaction tank of the sludge acclimating device; controlling the aeration amount to be 1-3 L/L/minute; carrying out acclimating for 10-15 periods in the acclimating period: feeding water, carrying out aerobic aeration, discharging sludge, depositing and draining water, obtaining stable-acclimated sludge; (b) adding the sludge to the synthetic reaction tank; taking acetic acid as carbon source, regulating pH to be 5.0-11.0; accumulating poly-hydroxyl fatty acid ester (PHA) by cycle intermittent method: carrying out aeration, stopping aeration and stirring, obtaining polyhydroxyalkanoic ester.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the reaction device for acclimating sludge and synthesizing polyhydroxyalkanoic ester.