Lean burn premixed charge stirred chemical reactor based combustion engines have developed to simultaneously reduce oxides of nitrogen (NOx) and soot from engine. Estimation of the in-cylinder nitric oxide (NO) in these engines is needed to understand its effects on the combustion phasing of these engines in modifying the ignition and combustion kinetic via NO-promoted production of OH radical, HO2 + NO ↔ OH + NO2. In the present work, modelling work on NO formation in the premixed charge stirred chemical reactor combustion based engine is presented. Firstly, the current understanding about the kinetics of accelerating and inhibiting effect of NO and its formation is presented. Secondly, factors (reaction rates and heat transfer coefficient) affecting in-cylinder NO formation were investigated and quantified. Thirdly, the relationship between the in-cylinder NO formation with in-cylinder heat transfer, combustion duration, charge inlet temperature and pressure were established. Finally, the impacts of parameters currently used for controlling in-cylinder combustion characteristics was investigated and presented for NO formation inside engine cylinders.