Affected by factors such as distance and observation conditions, ground-based facilities have limited ability to observe high-orbit space targets, but space-based observation facilities can effectively break through the observation limitations of ground-based facilities, thereby improving the efficiency and accuracy of observation of high-orbit space targets. Based on this, combined with the current status of space-based measurement technology, the method for determining the orbit of high-orbit space targets based on space-based optical angle measurement, including the initial orbit determination method and the orbit improvement method, is studied. In view of the influence of the observation type on the orbit determination result, the orbit improvement method that directly uses the space-based observation angle and the orbit improvement method based on the space-based observation direction vector are deduced. The two improved methods are compared with simulated data and measured data. The research results show that the orbit accuracy obtained from the space-based observation direction vector calculation is relatively high, which can provide a useful reference for the construction of space situation awareness system.