In this paper, we try to describe dynamic transition process in novices' computer programming based on goal/plan analysis. First, we design psychological experiments, in which subjects' programming process is recorded by both a tape recorder and a video camera. Secondly, we analyze subjects' semantic protocols, and convert the programming process into a series of scenes, each of which corresponds to a subject's thinking state. Thirdly, each of scenes is labeled based on categories established in advance. Through analysis of a series of labeled scenes, we identified six kinds of transition patterns in programming process, that is, (1) S-Process where syntactic error is recovered, (2) M-Process, semantic error is recovered, (3) T-Process, knowledge is acquired through tutoring, (4) F-Process, some different procedures appear one after the other without interaction with external environment, (5) R-Process, correct procedures which were applied previously are reinspected and (6) N-Process, some irrelevant procedures are applied continuously. We can explain successfully the regularity in novices' computer programming based on the six kinds of process. Moreover, through detailed observations of the six kinds of process above, we explicate the state of novices' knowledge on computer programming and acquisition and elaboration process of the knowledge. That is, when there are no relevant plans to solve a certain goal in subjects' knowledge base, it is pretty difficult for novices to construct a new plan by their own effort. In this case, tutor's instruction is an important factor to acquire the knowledge. Even when there are relevant plans, the plans have a lot of errors and large ambiguities, so novices must correct the errors and reduce the ambiguities. In this case, some kinds of messages from computer system : for example, compile error message, erroneous results of computation, become more prominent than tutor's instruction to correct the knowledge. We explain the role of those kinds of interactions with external environment (tutor's instruction, messages from computer system). We also explicate developmental process with continuous learning, where novices acquire more plans to solve a lot of goals, reduce ambiguity of the plans, and establish the correct knowledge base related to computer programming.