Myrmecochory is a widespread and important ecological interaction in which ants benefit by obtaining nutrition from lipid-rich elaiosomes attached to seeds. Plants benefit from having their seeds dispersed from parent plants. Given that ants are generally polyphagous, we hypothesized that the availability of alternative food resources other than the diaspore itself may influence ant-mediated seed dispersal. We used the myrmecochore Corydalis giraldii Fedde (Papaveraceae), the seeds of which are attached to a lipid-rich elaiosome that is attractive to ants, to investigate: (1) whether dispersing ants are more prone to alternative resources than the diaspore itself; and (2) how the availability of alternative resources affects ant activity and feeding preference, and, hence, ant visiting frequency to seeds and the rate of seed removal. In a field experiment, the pitfall trapping method was used to examine ant feeding preference among five dietary items (i.e. meat, honey, apple, bread, and seed of C. giraldii). Additionally, two artificial diaspore depots were offered near the ant nests, one with seeds and the other with either meat, honey, bread, apple fragments, or no food (control), to determine the effect of alternative food resources on seed removal. While eight ant taxa (ca. 837 individuals) were captured in the sampling plots, only two species (Lasius alienus and Formica fusca) were dominant and effective dispersers, with mass recruitment and simple cooperative recruitment, respectively. In fifteen 40-minute trials, the mean number of ant visits to the seeds was 38.73±4.57 times, and the mean rate of seed removal was 33.87±4.22 in L. alienus. No significant difference in either ant visit frequency or seed removal rate was found in L. alienus following the addition of alternative food types (P > 0.05). Both ant visit frequency and the rate of seed removal in F. fusca were reduced significantly by the addition of alternative food (P < 0.05). In particular, ant visit frequency decreased from the mean of 30.8±2.87 individuals (n=15, 40 min) in the control to 15.6 ± 3.61, 9.07±1.4,and 7.67±1.58 individuals with the addition of bread, apple fragments, and honey, respectively. The rate of seed removal decreased from 16.27±3.35 individuals (n=15, 40 min) in the control to 3.47±1.17 and 2.87±0.9 with the addition of apple fragments or honey, respectively. This suggested that the frequency of ant visits and removal rate of seeds in F. fusca strongly differed from that in L. alienus when alternative foods were presented along with the plant. We concluded that the indirect effects of alternative resources on seed dispersal depended on ant identity and its recruitment mode, contributing to the understanding of the fate of diaspores adapted for ant dispersal.