By using a method for synchronously-detecting gastric myoelectric activity and intraluminal pressure and a radioimmunoassay of plasmic motilin, gastric motility, plasmic level of motilin and their relationship in 12 normal individuals and in the patients with a variety of Spleen-Deficiency (SD) Syndromes, i.e. 12 SD with Cold type (H type), 7 SD with Stomach-Yin-Deficiency type(I type), 38 SD with Heat type (R type) and 6 SD with Liver-Qi-Stagnation type (U Type) were investigated. The results showed: degree of myoelectric dysrhythmia and rate of electro-mechanical decouple in all patients (except for I type) were much higher than those in the normals (P < 0.01 or P < 0.05); both mean frequency and amplitude of contraction in the patients were decreased; percentage of contractive action in the patients (except for I type) was lower than that in the normals (P < 0.05); plasmic level of motilin in the patients (except for I type) had a tendency to increase and had a linear correlation to degree of myoelectric dysrhythmia (r = 0.33, P < 0.01). It was suggested that some significant disorders of gastric motility exist in different SD patients and there might be an intrinsic cause effect relationship among increased plasmic motilin, myoelectric dysrhythmia and abnormal mechanical motion. The similar changes suggested that there is pathophysiological mechanism of SD syndrome. Furthermore, this synchronously-detecting method was useful to discover intrinsic relationship between gastric myoelectric activity and mechanical motion.