Transdermal drug delivery system has various merits compared to oral drug delivery system. Polyurethane nonwovens have been attracted as backing materials for patch and wound dressing, as they have superior stretchability and breathablility to films. The previous works on thermoplastic polyurethane nonwovens were mainly focused on the effects of meltblow processing parameters rather than pore, through which the infection can be occurred. It is critical to reduce the pore size without sacrificing the air permeability. In this study, we developed polyurethane composite nonwovens by combining the meltblowing and electrospinning processes. The composite nonwoven showed less than $3{mu}m$ of mean pore diameter with maintaining the air permeability. The load-elongation curve showed excellent adhesion between the meltblown and the electrospun layers even at large elongation. The excellent pore properties and stretchability of the composite nonwoven can be very useful for patch backing materials.