Multivariate data analysis (MVDA), a new statistical approach in terms of landfill research, was performed on the evaluation of three investigations. It gains advantage over classical statistical methods when multiple variables and their interactions have to be considered. In addition, it is tolerant for incomplete datasets. MVDA techniques as follows were applied: principal component analysis (PCA), partial least squares modelling (PLS) and partial least squares discriminant analysis (PLS-DA). The interrelationships among variables as well as variation between observations could be examined and illustrated by a few plots.