The crystallization properties of as-deposited amorphous AgInSbTe thin films irradiated by single-shot picosecond laser pulses were studied using in-situ transient optical reflectance and electrical resistance measurements with nanosecond resolution. It was found that the real-time optical and electrical signal responses were different under the same pumping conditions. The optical signals showed a multistage crystallization process with a total time of approximately 150 ns, while the electrical signals showed a negative exponential trend decreasing to the final stable state within about several microseconds. A resistor–capacitor model was constructed to explain this delayed electrical response. The fluencedependent evolution dynamics maybe implied a non-fully crystallization process under ultra-short pulse stimulation.