In the application of biological tissue engineering,three-dimensional and longitudinal evaluation of biological structural markers is needed.However,these biological structures are usually several millimeters thick and cloudy,thus,it is very challenging for imaging,and classical fluorescence microscopy can not meet its needs.Therefore,we developed a mesoscopic fluorescence molecular tomography method.Mesoscopic fluorescence molecular imaging system was a new imaging system,which filled the gap between microfluorescence molecular imaging technology and macrofluorescence molecular imaging technology.In order to improve the performance of mesoscopic fluorescence molecular reconstruction,this paper mainly improved the configuration of the system.The configuration parameters of the optical system,including detector layout,uncoupled or coupled scanning mode,were optimized based on optical principles,and the 3d imaging performance of the mesoscopic fluorescent molecular imaging system was evaluated and compared.The results show that the coupling backlight mesoscopic fluorescence molecular tomography imaging (MFMT) system designed in this paper can improve the reconstruction performance and obtain high-quality reconstruction results.