Polycaprolactone/poly (L-lactic acid) composite micro/nanofibrous membranes (PPA) were prepared through solution blow spinning (SBS), using biodegradable poly (L-lactic acid) (PLLA) and polycaprolactone (PCL) as the raw materials. PPA were characterized with FTIR, SEM, XPS, TGA, and XRD. The effects of SBS parameters on the morphology, porosity, density, mechanical property and oil adsorption properties of PPA were investigated. PPA with different mass ratio of PCL/PLLA had different fiber diameter and porosity. PPA with PCL/PLLA mass ratio 1:4 expressed higher oil adsorption capacity than the raw materials, being 24.56 g/g, 14.54 g/g and 13.28 g/g to crude oil, peanut oil and diesel oil, respectively. The oil adsorption capacity could remain about 50% after 10 cycles of reuse. PPA had good hydrophobicity (water contact angle up to 155 degrees and oil/water adsorption selectivity 26:1). The obtained PPA membrane is potential as adsorbent to separate oil from oil/water mixture.