The reserves were down by $113.5 million to $353.347 billion in the previous reporting week after touching an all-time high of $355.46 billion in the week to June 19.
Foreign currency assets (FCAs), a major component of overall reserves, rose by $1.039 billion to $330.836 billion in the reporting week, according to the latest 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 the yen, held in the reserves.
Despite a massive drop in gold prices, the reserves of the yellow metal stood unchanged at $18.250 billion.
India's special drawing rights with the International Monetary Fund rose $35.4 million to touch $4.055 billion in the week under review, while the nation's reserve position with the Fund also rose by $11.2 million to $1.291 billion, the apex bank said.