This paper investigates and discusses the effect of key geological factors on diagenesis. Siliceous artificial sands are chosen as object of study. Response characteristics of diagenesis to temperature, pressure, and time are quantitatively studied from the perspective of forward physical simulation. The results indicate that, the compaction of siliceous artificial sandstones increases with pressure and temperature. Temperature has the most significant effect on the crystallinity of authigenic minerals like quartz. In the simulation, the transformation of amorphous silica to crystalline occurs under the temperature of 400℃. In a certain range of temperatures, there is a parabolic correlation between mineral crystalline and pressure, with a dominant pressure range. Best pressure for siliceous crystalline is around 137.5MPa. The pressure contributes to diagenesis in two ways, i.e., compaction and thermal effect of which the former is more significant. During the process of diagenesis, longer reaction time may compensate temperature and pressure. Reaction time has greater effects on chemical diagenesis than compaction. Results of this research are of great reference value for diagenesis numerical simulation, quantitative study, and further research in mechanisms of diagenesis.