A portable CE system was developed for the identification of cattle breeds. The system had a width of 44 cm, depth of 27 cm, height of 13 cm, and a weight of only similar to 8 kg and included an LIF detector, with everything integrated into a small box. The specific sizes of genes were quickly separated and detected with a high sensitivity based on the difference in the DNA mobility using a diode-pumped solid-state LIE detector. Using this system, the 100-bp DNA ladder was analyzed under a 1.0% PVP (M-r = 300 000) sieving gel matrix in a fused silica capillary with LODs of 4.4-13.0 pg/mu L (S/N = 3) for 100-3000 bp DNAs, which indicates ten times improved value than other commercialized portable CE system. The migration times and the peak areas showed good reproducibilities with relative standard deviations that were less than 0.49 and 1.3% (n = 5), respectively. Based on the difference in the DNA mobility of the microsatellite and SNP markers, Korean cattle and Holstein were exactly identified as the model cattle breeds within 32 and 3.5 min, respectively.