Livelihood is sustainable when it can cope with and recover from shocks and stresses and also maintain or enhances its capabilities and assets now and in the future while not undermining the natural resource base. The risk of livelihood failure determines the level of vulnerability of a household to income, food, health and nutritional insecurity. The rural livelihood diversification is an integral dimension of development agenda for strengthening rural livelihood and sustaining livelihood security. The present study was conducted among 120 households in two islands of U.T. of Lakshadweep for the socio-economic assessment of major livelihood adaptations. Randomly selected 120 respondents were categorized into three categories based on their livelihood strategies in terms of share of agriculture in household's income. Farming group represented the first group, the respondents having non-farm based livelihood options represented the second group and both farming and non-farming households represented the third group. Study examined the average annual income change over the period using paired t-test of two sample data. It was observed that it was significantly changed over the period for three groups. Seven components of livelihood security were also analyzed using Wilcoxon Signed Rank test and found that food security, habitat security, educational security and health security of the three groups were significantly changed and social security was not significantly changed. For second group, environmental security was also changed significantly. For only farming group occupational and financial security was not significantly different.