Laser welding has improved the manufacturing productivity and made a great opportunity over conventional joining methods. Producing hybrid metal-polymer components is drawing more attention in terms of their aptitude specifically in the aerospace and automotive industries. The joining of a hybrid metal and a polymer can be troublesome due to some drawbacks in chemical and physical properties or incompatible structures. Diverse techniques are applied for joining dissimilar materials, specifically polymers and metals with the purpose of achieving high flexibility. Laser welding is an effective technology to join dissimilar materials with considerable advantages such as flexibility, low environmental impacts, noncontact, high speed, and accuracy. In fact, the main challenge for manufacturers is still on how to choose the input process parameters to get the best joint performance. This paper investigates an experimental study of dissimilar welding of transparent Poly(ethylene terephthalate) to aluminum 7075 sheets by a diode laser. Laser joining parameters play a crucial role in determining the quality of joining between PET films and aluminum plates. In the present work, laser power and scan speed were considered as operational parameters, which have a significant influence on the quality of the joint zone. Laser transmission joining was optimized using response methodology for achieving good joint strength with minimal barriers.