The reserves had surged by $236.4 million to $319.475 billion in the previous week.
The previous life-time high for the reserves was $320.79 billion, way back in the week to September 2, 2011.
The foreign currency assets, a major constituent of overall reserves, jumped $2.685 billion to $297.53 billion in the reporting week, as per the Reserve Bank data.
FCAs, expressed in dollar terms, include the effect of appreciation and depreciation of non-US currencies such as the euro, pound and yen, held in reserves.
The country's gold reserves remained unchanged at $19.377 billion.
Special drawing rights decreased by $19.3 million to $4.109 billion, while India's reserve position with the InternaMF dipped by $5.2 million to $1.118 billion during the week, the data showed.