A share/stock reaching 52 week low is mostly considered as opportunity to invest as a undervalued stock. However, 52 week low stocks must be thoroughly analysed before investing i.e an investor must look into the fundamentals, financials (Balance sheet, P&L statement, cashflow etc.) and technical charts before investing in 52W low stocks. Investing in 52 week low stocks may sound like a potential opportunity. At the same time you must evaluate the risk associated with it as well. Only considering a day's movement of price change may not be a good investing factor.