Speech-Synthesis-System. Language is the structural form of sharing thoughts and emotions in humans. The research motivates to stroke up for the Human-computer interaction. The overall intention of my PhD research program is focused to design Concatenation and Hidden Markov Model (HMM) based speech synthesis for the Marathi language. This will facilitate to correspond to the system and extend the technology for assertive devices based on the Marathi language. The advantage and attractive feature of the HMM system are that the voice alteration can be performed without large databases. To understand the detailed study of Synthesis techniques, I have also implemented the system for Unit Selection method. The Marathi Talking calculator is published at Play store using the technique of concatenation. This calculator performs the basic arithmetic operations and additionally speaks out the numeral in Marathi as the key is pressed. The result box synthesis the voice and speaks out the result in Marathi with correct place value of digits. The weakness of USS is it requires a large database and at joins, the quality is affected. To overcome these issues, the study reveals the built-up of a system with a phonetic based approach for Marathi Language using Concatenation and HMM.