Detection of latent fingerprints is one of the key steps in material evidence detection. On the basis of the characteristic that the organic components of latent fingerprints will produce fluorescence under ultraviolet excitation, the two-dimensional laser scanning system is adopted to scan the latent fingerprints left on the surface of porous paper with high speed (the 266 nm ultraviolet laser is used as excitation light source). Interference light is filtered by narrow band filter. The experimental parameters are optimized according to the fingerprint stripe contrast, the latent fingerprint fluorescence images is reconstructed by the methods of removing the singular highlights and enhancing the fingerprint stripe contrast. By above methods, clear images of the sweat fingerprints and sebaceous fingerprints left on the surface of five types of porous paper (copy paper, writing paper, student work paper, sticky note and newspaper) can be obtained. The method can realize the non-destructive detection of latent fingerprints on the porous paper. It has important applications in many fields such as criminal investigation and trace detection.