The photovoltaic behaviors ahve been observed with a sandwich-type cell, consisting of a junction between .betha.-carotene and stannic oxide conducting layer to provide a junction electrode. In the stannic oxide and .betha.-carotene junction it was found that its electromotive forse decreased to a value smaller than the original one. This is due to a space charge formation. Photovoltage reached approximately 40mV with an irradiation energy of 250Kcal/M$^{2}$hr. It appeared that a magnitude of the photovoltaic response was proportional to the logarithm of irradiance. The time constant of the photovoltaic effect was shown to be approximately 0.7 sec. The wavelength dependence of the photovoltaic behavior was very anomalous. It is assumed that such an anomalous photoresponse depends on a internal capacitance due to some bubble during process to make a cell.