The growing issues of energy shortage and the environmental crisis have resulted in new challenges for the automotive industry. Conventional commercial vehicles such as refuse trucks and delivery vehicles consume significantly more energy than other on-road vehicles, and emit more emissions since those types of vehicles have the characteristic of frequent start/stop with high moment of inertia and drive at low speeds on designated city routes. It is important to make these vehicles more fuel efficient and environmentally friendly. The hybrid commercial vehicle is a promising solution to reduce emission and to meet the future vehicle emission standard since it is generally equipped with braking energy regeneration systems to recover the kinematic loss from frequent braking. This paper introduces a type of four-wheel drive architecture designed by Dr. Oriet, Leo; this architecture equipped with 4 traction motors, a ISG unit, diesel engine and a hybrid power source which allows commercial vehicles have a significant improvement in terms of braking safety, maximizing the capability of two axles regenerative braking as well as dynamic performance. Due to the fact that no mechanical connection is involved to transfer energy within the powertrain, great powertrain efficiency can be achieved in this architecture. The research is based on this four-wheel drive architecture study to propose the key components parameters and control strategy. These include power component parameters calculation, energy management strategy and powertrain diagnosis. The control strategy and regenerative braking will offer detailed information. The vehicle model and driveline control unit will be executed by AVL CRUISE to demonstrate its reliable braking energy regeneration system, effective energy management and emission reduction. Moreover, the engine and ISG unit operating efficiency, as well as powertrain energy flow, will be analyzed after simulation. Finally, the current battery technology, BMS unit and safety prevention will be indicated along with the Pros and Cons of a four-wheel drive commercial vehicles.