Introduction: The main obstacle for tissue engineering is to find the most appropriate cell which is able to produce extracellular matrix (ECM) similar or better than natural chondrocytes in vitro. This study compared aggrecan synthesis′s potential between differentiated chondrocytes (DCs) from adipose-derived stem cells (ADSCs) and natural articular chondrocytes (NCs) in 3D culture in vitro. Materials and Methods: Human ADSCs were isolated from sub-cutaneous adipose tissue and then the surface markers including CD 14, 45 CD105, CD90, CD44 were analyzed by flow cytometry. Also human articular chondrocytes were yielded of non-weight bearing area of Knee cartilage. Both types of the cells were encapsulated in alginate scaffolds and cultured in chondrogenic medium with and without TGFβ3 for 3 weeks. Then the extent of aggercan (AGC) production was evaluated by ELISA on days 14 and 21. Results: Our findings indicated that differentiated chondrocytes (DCs) with and without TGFβ3 synthesized more AGC than natural chondrocytes (NCs) on day 14. But DCs without TGFβ3 had higher production than other groups on day 21. Application of TGFβ3 resulted in an increase of amount of AGC in DCs on day 14 but a decrease on day 21 than same group. Conclusion: Since, aggrecan is an important chondrogenic marker, it was concluded that ADSCs can be possible reliable alternative cell source for cartilage tissue engineering in future.