This study investigated the difference of antioxidants activity from different extraction techniques of Jerusalem artichoke (Helianthus tuberosus). Three different extraction techniques involved were aqueous extraction, autoclave-assisted extraction and 70% ethanol extraction. Total phenolic content (TPC) was determined using the Folin-Ciocalteu method. The antioxidant activities were analysed using ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH). The autoclave-assisted extract showed the highest total phenolic content and both FRAP and DPPH activities at 127.87  0.08 mg GAE/g, 53.38  2.76 mg AAE/g and 79.92  0.26 mg AAE/g, respectively. Meanwhile, the aqueous extracts showed 2-fold higher total phenolic content compared to the ethanol extracts at 65.73  9.44 and 30.61  0.00 mg GAE/g. Conversely, antioxidant activities obtained from the ethanol extracts (41.49  2.54 and 41.10  0.10 mg AAE/g) were higher compared to the aqueous extracts (23.29  0.47 and 5.24  0.38 mg AAE/g.). This study suggests that different extraction methods influenced the findings of total phenolic content and antioxidant activities of the Jerusalem artichoke. Among three different extraction methods, the results suggest that the effect of autoclave-assisted extraction is more effective for the antioxidant extraction from Jerusalem artichoke than aqueous and 70% ethanol extraction. Hence, Jerusalem artichoke can be considered as a potential source of natural antioxidants.