There has been concern over the ecotoxicity of residual pharmaceuticals detected in the aquatic environments. Paracetamol (acetaminophen) is one the most extensively used over-the-counter drugs and its residues have been detected in the aquatic environment. There have been contradictory reports on the sensitivity of microalgae to paracetamol (PCM). The primary aim of this study was to assess the toxicity of PCM in five microalgae, namely Pseudokirchneriella subcapitata, Scenedesmus dimorphus, Stichococcus bacillaris, Chlorella vulgaris, and Chlamydomonas reinhardtii based on 96 h test at concentrations ranging from 0, 30, 60, 120, to 240 mg L^-1. Results showed that the microalgae were very resistant to PCM as the EC₅₀ values based on OD₆₂₀ were beyond the highest concentration (>240 mg L^-1) tested. However, P. subcapitata was more sensitive than the other species when compared using EC₁₀ (91.4 mg L^-1) based on chlorophyll a (chl a) concentration. Both chl a and total carotenoid concentrations of Psedokirchneriella subcapitata and Scenedesmus dimorphus exposed to the highest PCM concentration (240 mg L^-1) were significantly (p<0.05) lower than the control. In comparison, the car:chl a ratio of Chlorella vulgaris increased with increasing PCM concentrations.