Laser-induced ultrafast photovoltaic effect is observed in LaSrAlO4 single crystal at ambient temperature without any applied bias. An open-circuit photovoltage is obtained when the wafer is irradiated by a 248-nm-KrF laser pulse of 20 ns duration. The response time and full width at half maximum of the photovoltage pulse are 6 ns and 19 ns, respectively, indicating that LaSrAlO4 single crystal has potential application in ultraviolet detector. Laser-induced ultrafast photovoltaic effect was observed in LaSrAlO4 single crystal at ambient temperature without any applied bias. An open-circuit photovoltage was obtained when the wafer was irradiated by a 248-nm-KrF laser pulse of 20 ns duration. The response time and full width at half maximum of the photovoltage pulses are 6 ns and 19 ns, respectively, indicating that LaSrAlO single crystal has potential application in ultraviolet detector.