An analytical model is established based on the Wiener-Hopf (W-H) technique in conjunction with the mode-matching method to predict the noise radiated from traffic tunnels. Multiple point sources with different locations and volume velocity strengths are applied to simulate the sound produced by vehicles. In the first place, the sound field inside a tunnel is expressed in terms of normal modes while the radiated sound field outside the tunnel is converted from the natural domain to the spectral domain through the Fourier transform. Subsequently, a scalar modified Wiener-Hopf equation (MWHE) of the second kind is obtained and solved following the standard decomposition and factorization procedures. After that, the unknown coefficients are determined adopting the continuity relations of pressure and particle velocity at the opening and the far-field directivity patterns of the radiated sound field are then attained via the inverse Fourier transform which contains a complex integral that can be evaluated by the saddle point method approximately. Finally, the model is validated by the finite element method (FEM), and the formation mechanisms of the radiated sound fields are investigated, which will be useful for the proposal of appropriate noise control approaches.