A water-penetrable drip irrigation pipe includes: a buffer tube having a water-penetrable fibrous core member clad in the buffer tube which is lengthwise formed in a main pipe as contiguous to an inside wall of the main pipe, having a plurality of water inlet holes respectively spaced apart and longitudinally formed in a bottom of the buffer tube to communicate with an interior in the main pipe, and a plurality of drip outlet holes longitudinally formed in the main pipe, whereby the water flowing in the interior of the main pipe will penetrate the fibrous core member in the buffer tube to be filtered by and frictionally dampened by the fibrous core member for discharging clean irrigation drips having decreased pressure.