By combining the numerical-parameterized optimized effective potential (NPOEP) model and pseudospectral method, the high-harmonics generation(HHG) process of alkaline metal atoms in intense laser field is investigated. The evolution matrix is modified based on the features of NPOEP model. The orthogonality of time-dependent wave function with closed-shell orbit in evolution process is ensured. The mid-infrared laser field with a wavelength of 3038 nm and intensity of about 1013 W/cm2 is chosen as the driving field, and the high-order-harmonic spectra of lithium, sodium and potassium atoms are calculated. Contributions of bound state transition harmonics of Rydberg state sodium atom on harmonic generation are investigated. Results show that the resonance of Rydberg and ground state can make the low-order harmonic intensity increase by one order of magnitude. It is verified that the method is reliable in describing the process of electron recapture during time evolution.