Implementing green analytical techniques has been one of the main objectives of the analytical chemistry community for the past two decades. The aim of transitioning to green analytical chemistry is to establish new methods environmentally benign instead of traditional methods. According to WHO, 20 million people worldwide are affected by schizophrenia, and 45 million people worldwide are affected by bipolar disorders. For that, in this work we develop a green HPTLC method to quantify simultaneously the four antipsychotics chloropromazine HCl, asenapine maleate, quetiapine fumarate and aripiprazole in pure form and tablet formulations. In this chromatographic method, separation was performed using silica gel 60 F254 HPTLC plates, the mobile phase composed of binary mixture of green solvents (ethanol : water (9 : 1 v/v)) which gave compact band with Rf values ranged between 0.14 to 0.70 for the drugs. The method was validated for linearity, accuracy, precision, selectivity and robustness according to ICH guidelines. It was assessed for greenness by analytical Eco-scale and compared with reported HPTLC methods for single analysis of these antipsychotics.