Like anything, there is a variety of disadvantages in investing stocks. We are going to explore three risks including unexpected risks by changing economy, gambling addiction and relying on luck, not” brain” in stock investment. Originally, investing in stock market is riskier than other types of investments. Stock is not the safe type investment all the time. It means that if you are knowledgeable enough to invest stocks, you also can’t control some situations that happen unexpectedly by changing economy. For example, the attack on September, 11th 2001 had a significant impact on the United States and world economy. Many largest stock exchanges in US had to close until 17th September such as New York Stock Exchange, NASDAQ (National Association of Securities Dealers Automated Quotation System). When these stock exchanges opened, the stock market index fell sharply and not only affected investors, but also to those companies who issued stocks. Many investors were deep in debt and companies bankrupted on that day. The second major risk of stock investment is stock gambling addiction. Investor will turn themselves to gamblers even when they win or lose. They can’t control themselves and play stocks until losing everything. Because like other kinds of gambling such as playing cards, betting on horses or football, Stock gambling may make people addictive in earning money and it will lead to uncontrollability. Something unseen inside their heart will push them to try another time even they won or lost. Finally, even people have knowledge in investment; they always intend to rely on their luck rather than their knowledge and capability. As a result, sometime their heart could lead up to have wrong decisions in investing. Wrong decisions might lead up to bankruptcy.