PURPOSE: To smoothly perform the molding at start and consequently prevent defective product from developing by a method wherein injection molding is done by collating the molding conditions and monitoring conditions with data stored in the memory of an electronic controlling device and actual result data are gathered in said memory so as to be transferred to an injection molding on the basis of the next molding conditions on reference to said data.

CONSTITUTION: Injection molding is done on molding conditions A, which are obtained by reading data stored in a memory part of molding conditions at start 10-5 and actual result data are stored in a memory part of actual result data 10-2. By collating stored data with instructed data, the proceeding to next stage is judged to be possible or not. When the proceeding to next stage is intended, injection molding is done on the basis of molding conditions B, which are in line with basic molding conditions and, after the elapse of time T1 with a timer 10-6, changed. The actual result data at that time are stored in the memory part of actual result data 10-2. By comparing stored data with instructed data, the proceeding to next stage is judged again to be possible or not. The actual results of molding are stored without a break. If abnormality is judged, alarm is issued by an alarming device 18 and, at the same time, controlling is done by automatically changing the molding conditions to those as was before change and the like.