In order to further optimize the liquid Terahertz radiation source induced by femtosecond laser, a femtosecond laser-induced liquid line radiation Terahertz wave experimental system was designed. Combined with quantum chemistry calculation and femtosecond laser-induced liquid line radiation Terahertz wave experiment, the relationship between the microscopic and macroscopic characteristics of the excited medium and the Terahertz electric field was studied. The experimental and calculated results show that the Terahertz electric field is negatively correlated with band gap width and dipole moment. The nonlinear trend of Terahertz electric field with solution concentration is related to the density and Reynolds number of the medium, and the optimal volume fraction of Terahertz wave electric field is 40%.