Laser metal deposition process is one of the important processes of additive manufacturing technology which is used for the production of end-use parts as well as repair of worn-out high valued engineered parts. The functional performance of laser metal deposition process is greatly dependent on its process parameters; therefore, considering the type of job and nature of material, they need to be adequately optimized before a job can be successfully carried out and with the desired properties. The processing parameters that govern the laser metal deposition process include: the laser power, the scanning speed, the powder flow rate and the gas flow rate. A lot of interactions exist among these processing parameters that make the careful optimization of the processing parameters an important task. In this chapter, modelling of laser metal deposition process of metal alloys and composites is presented. The chapter consist of an in depth review of literature on this subject in the introduction (Sect. 1). Optimization of process parameters for laser metal deposition of titanium alloy is presented in Sect. 2. A case study on statistical modelling of titanium alloy composite and process parameters optimization is presented in Sect. 3. The chapter ends with the summary in Sect. 4.