Taking α-asarone as model drug, mono methoxy polyethylene glycol-polylactic acid copolymer (mPEG-PLA) as the drug carrier material to prepare drug-loading nanoparticles by premix membrane emulsification for nasal administration. The prepared nanoparticles were spherical with smooth surface and average particle size of 360 nm. Polydispersity index (PDI) was 0. 030, average drug loading of (11.5 ± 0.045) % (n = 3), and the encapsulation efficiency of (86.34 ± 0.11) % (n = 3). X-ray diffraction and differential scanning calorimetry results showed that, α-asarone existed in mPEG-PLA carrier in amorphous or molecular state, different from simple physical mixture. In the in vitro release test in simulated human nasal cavity, α-asarone apis can be released quickly at close to 94% at 102 h, in line with the first-order kinetics (R² = 0.981 9). mPEG-PLA drug-loading nanoparticles release only 54%, with slow release effect, in line with Riger-Peppas model (R² = 0.967 9, n = 0.630 2), for non-fick diffusion, released by the spread of drugs and skeleton dissolution dual control. This provided the foundation for nasal drug delivery in vivo pharmacokinetic study.