The economic development of a nation is reflected by the progress of the various economic units, broadly classified into corporate sector, government and household sector. There are areas or people with surplus funds and there are those with a deficit. A financial system or financial sector functions as an intermediary and facilitates the flow of funds from the areas of surplus to the areas of deficit. A Financial System is a composition of various institutions, markets, regulations and laws, practices, money manager, analysts, transactions and claims and liabilities. In this Paper researcher identified the various factors & Biases, which are affected for choice of Assets allocation and perceptions of investors related to investment decision by analysing various literature & books of related study.