UV spectrophotometric and high performance liquid chromatography (HPLC) methods were developed for simultaneous determination of meropenem (MERM) and sulbactam sodium (SB) in injection. UV spectrophotometric methods were developed using 0.1N sodium hydroxide as solvent. The Beer's plot for dual wavelength method was linear in the range of 4-24μgmL - 1 and 2-12μgmL - 1 for MERM and SB, respectively. The percent recoveries were found to be 98.52+/-1.23% for MERM and 101.45+/-1.1% for SB. Chemometrics assisted UV spectrophotometry was performed using Partial Least Square (PLS) analysis model and Principal Component Regression (PCR) analysis model. The % recoveries of the MERM were found to be 100.61+/-0.06% and 101.31+/-0.12% using PLS and PCR, respectively. The % recoveries of the SB were found to be 98.29+/-0.09% and 97.61+/-0.13% using PLS and PCR, respectively. Chromatography was performed on Hypersil BDS C18 column using methanol:acetonitrile:water (10:20:70 v/v/v) as mobile phase. The retention times of MERM and SB were found to be 2.9min and 2.25min, respectively. Developed HPLC method was found to be linear in the range of 50-250μgmL - 1 and 25-125μgmL - 1 for MERM and SB, respectively. The % recoveries were found to be 98.85+/-0.25% and 98.63+/-0.34% for MERM and SB, respectively. The developed analytical methods did not show any interference of the excipients when applied to pharmaceutical dosage form.