Parameter setting method and monitoring apparatus using the method

In a monitoring apparatus for monitoring an object which intrudes into a monitoring subject area by using an image pickup device, it is demanded to adjust parameters according to conditions such as the monitoring purpose and the surrounding environment in order to execute suitable monitoring. To this end, in the monitoring apparatus, parameters corresponding to monitoring conditions are subject to grouping. Suitable values of parameters in each group obtained by the grouping are previously determined according to a degree of a monitoring condition. A monitoring condition and its degree are selected by using an ordering device having user interface components such as push buttons mounted thereon. It is made possible to instantaneously alter parameters belonging to a group corresponding to the monitoring condition all at once at this time. Parameter adjustment free from troublesomeness and skill is thus implemented.