Pastoralists' livelihood was threatened by Prosopis invasion of farm and pastor land in the study area of Afar region. Thus, this research paper aimed to deliver empirical evidence on the links between household perception regarding Prosopis juliflora, and pastoral livelihood diversification strategy. Determinants were empirically analyzed using multinomial logit model (MLOGIT) and two step Tobit regression model (IVTOBIT). The results indicate that the household perception vary widely over the sample, showing a significant positive effect on their livelihood diversification. Even if the majority of households prefer to stay on livestock production, some sample households began crop production with increasing returns. A strong positive correlation between the household perception regarding the species and their livelihood diversification strategy as well as complementarities was revealed between crop and livestock production. Accordingly these suggest that perception of household that consider it as good and livelihood diversification is conducive for controlling species invasion, environmental and livelihood sustainability in the study area.