Aloe vera, a popular succulent perennial medicinal plant with a wide range of phytochemicals that have shown various pharmacological activities including anti-oxidant, antimicrobial, antidiabetic, wound healing promotion and so on. Acemannan, aloe-emodin, aloin, aloesin, and emodin are widely investigated active constituents that show various pharmacological activities. Thus, the purpose of this review is to highlight previous pharmacological studied conducted in vivo, in vitro and human assays over the past decades. As current pharmacological research is focused on anticancer and neurological action, it would be interesting and important to study the main compounds present in Aloe vera for therapeutic purposes.