The current LC-MS/MS method was developed and validated for the estimation of Metformin in human plasma using Doravirine as an internal standard. Phenomenex Synergi, 4m, 4.675mm was used with an injection volume of 25 L, a run time of 20 minutes, and a mobile phase consisting of 5mM Ammonium Acetate buffer containing 0.1% Formic Acid: Acetonitrile (40:60 v/v) to achieve the best results using positive ion mode (API 4000Q Trap). Electrospray ionisation (ESI) tandem mass spectrometry operating in positive ion mode is used for detection at room temperature and atmospheric pressure. The precursor-to-product ion transitions of m/z452.42>71.32 for Metformin and m/z271.2>228.8 for Doravirine (Internal standard) were utilised for quantification. Doravirine (Internal standard) had a retention time of 1.56 minutes, while Metformin's was 7.04 minutes. Metformin's linearity was determined over a concentration range of 8.0 pg/mL to 160 pg/mL (r=0.999), and the drug's overall percentage recovery was 99.3% (compared to 100.7% for Doravirine, the internal standard). Accuracy and precision of the proposed method were determined to be within 15% CV for Metformin. Metformin stability studies found CV% values of accuracy and precision of 15%, indicating the proposed method is stable. Method specificity, precision, accuracy, linearity, robustness, reproducibility, and results dependability have all been demonstrated through the use of LC-MS in the course of this study's development and validation.