The choice of the most suitable statistical distribution for modeling data is very important. Generally, the new distributions are more flexible to model real data that present a high degree of skewness and kurtosis. In this paper, we define a new one-parameter lifetime distribution, so-called weighted-Lindley distribution. Some of its basic properties are investigated. Some classical and Bayesian methods of estimation have been used for estimating its parameter. The behavior of these estimators were investigated by a graphical simulation study. A real data set is analyzed to investigate the flexibility of the new weighted-Lindley distribution.