Nd:hosted lasers passively Q-switched or/and mode-locked by the plastics dye sheet, the LiF:F-2 colour centre crystal, the Cr4+:YAG crystal and the schott colour filter glass were investigated. A detail analysis of the mode-locking effect in combination with Q-switching was provided. Interpretations were given based on the characteristic features of the materials, like saturation intensity and relaxation time.