In this study, Arius maculatus were collected using the samples caught by bottom trawling off the southwestern coast of Taiwan. Length-weight and length-length, fork (FL), standard (SL) and total (TL) lengths, relationships were determined. The relationships between the lengths were all significantly linear (p<0.01), the b value in the length-weight relationship for this value was significantly lower than 3 in the fall (p<0.01), when the temporal changes were taken into account, indicating that only the sampling time affected the growth pattern of A. maculatus.