The study aims at reducing the drag produced over a flat surface. The motivation for the research comes from several aquatic animals which in spite of having huge weight have good manoeuvrability. Numerical simulations are performed to investigate the effect of micro-textured riblet surface for drag reduction over a flat surface. Effects of geometric as well as flow parameters on the drag are analysed. Validation of the non-dimensional geometric parameter is done by comparing the results of two different Reynolds number. Simulations are carried out by maintaining an external flow condition. Fundamental concepts which are responsible for drag reduction in micro-scale are studied. It is found that drag reduction is maximized in the spacing range of 15-20 turbulent wall units. Maximum drag reduction is found to be around 10% for sawtooth riblet profile. It is expected that optimized riblet could be used for experimental test and could be further implemented in real-life applications.