Pulsars are important for studying gravitational wave, the equations of state and the evolution of single stars and binary systems. However, there are still many aspects about pulsar that are unknown, such as the decay mechanism of magnetic filed of pulsar, the formation of binary pulsar and so on. In this thesis, we introduced the backgrounds of pulsar, the formation channel of binary pulsar. Then we emphatically introduced our work in details−a study about the formation of intermediate-mass binary pulsars (IMBPs) with short orbital periods（Porb）. An IMBP is made up of a neutron star (NS) and a CO/ONe WD. It is generallyaccepted that the IMBPs come from the evolution of intermediate-mass X-ray binaries (IMXBs). However, the IMXB scenario is difficult to account for the formation of those IMBPs with 𝑃orb < 3 d. It has recently been suggested that a system composed by a NS and a helium (He) star can form IMBPs with Porb < 3 d (NS+He star scenario). This work systematically studies the formation of IMBPs from NS+He star channel by adopting different NS masses and different descriptions of the Eddington accretion rate for NSs. We found that the NS+He star scenario is an important scenario for the formation of IMBPs with short orbital periods, which can explain the formation of most observed IMBPs with short orbital periods. Otherwise, we also found that the NS+Hestar scenario is an significant scenario for the formation of IMBPs with long orbital periods. The main results are followings:(1) The initial mass of NSs have impact on our results. An initially less massive neutron star will be spun-up to more fast spin under the same initial conditions.(2) Our results can cover about 80% the observed IMBPs with 𝑃orb < 3 d. Besides, the observed properties of about half of the IMBPs with 𝑃orb >3 dcan be also covered by our results.(3) Our results reproduce the observed properties of the system PSR J0621+1002 quite well and we display a possible evolutionary path of PSR J0621+1002.
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