After the multiwall carbon nanotubes are irradiated by a 1064 nm wavelength fiber laser, connection phenomenon is found by scanning electron microscope (SEM) observation. The SEM images clearly demonstrate the melting and solidified phenomenon between the two overlapping multi walled carbon nanotubes. Two or more multi wall carbon nanotube fuse together, and the tube wall is smooth and complete without any sign of damage. Through the transmission electron microscopy (TEM), the new graphite layers are found in the connection. Besides, It is found that in the case of a certain power density, as the laser irradiation time increases, the present multi-walled carbon nanotubes show the trend of melting connecting to destruction.