The present paper deals principally with the dynamics and difference of individual fecundity in the spring and autumn spawners of Large Yellow Croaker, collected in the periods from March-June and September-一October， 1959 from Taichu-Yang, Chekiang. 1n 304 spring spawners studied, the individua1 absolute fecundity ranges from 52.2 to1616.8 (× 1,000) (average 376.2); the individua1 relative fecundity r/q ranges from276.7 to 1005.9 (×1) (average 608.7) and r/1 from 2.1 to 32.7 (× 1,000) (average9.9). 1n 41 autumn spawners studied, the individual absolute fecundity ranges from156.1 to 601.2 (× 1,000) (average 286.8); the individua1 relative fecundity r/q from304.3 to 726.6 (×1) (average 459.5) and r/1 from 4.5 to 14.1 (× 1,000) (average 7.8). After analysing the relations of individual fecundity to weight (excluding the gut and the gonads) ， standard 1ength and age of this fish, we consider that: 1, The individual fecundity increases, but differently, with the increase of weight, length and age.2, 1t is closely associated with weight rather than with length and age. Therefore the main influential factor is growth.