This research aim to study investment behavior and To study the importance of choosing to invest in mutual funds to benefit through the securities fund management of the elderly in Bangkok. By collecting data, concept, theory and related document. Researcher stated 400 sampling of retirement mutual fund investors within Bangkok, use questionaire as a tools for collecting data in descriptive and quantitative analysis by frequency distributions, percentage, mean, standard deviation. Analyze data for statistical hypothesis Chi-Square (X2) and One-way ANOWA significant level 0.05