The study examined the effect of Cash Management Techniques on the Financial Sustainability of Manufacturing Firms in Nigeria. The specific objectives of this study are to; Examine the effect of Cash and cash equivalent on the Financial Sustainability of Manufacturing Firms in Nigeria. Evaluate the effect of the Cash flow adequacy ratio (CFAR) on the Financial Sustainability of Manufacturing Firms in Nigeria. An expost facto research design was adopted. Meanwhile, the data source is secondary. The paper generates annual time series panel data gathered from the Nigerian Exchange Group (NGX) for the period of 12 years, 2012-2023. The data was analyzed using Eviews 13.0. The result revealed that Cash and cash equivalent have a significant positive effect on the Financial Sustainability with a p-value less than 0.001 of Manufacturing Firms and Cash flow adequacy ratio (CFAR) has a significant effect on the Financial Sustainability with a p-value less than 0.0059 of Manufacturing Firms in Nigeria. The study concluded that cash management techniques have significant positive effects on the financial sustainability of manufacturing companies in Nigeria. The study recommended among others that Firms should strive to optimize liquidity by efficiently managing working capital, streamlining inventory control, and accelerating receivables collection.