A counterfeit-preventive optical element, comprising a first layer; a second layer having a refractive index different from a refractive index of the first layer; and a third layer partly welded or joined to the first layer, wherein the first layer, the second layer, and the third layer are stacked in this order, a relief structure is provided between the first layer and the second layer, the first layer at least includes a first region and a second region, an inclination angle of a first slope of the relief structure in the first region differs from an inclination angle of a second slope of the relief structure in the second region, the first region is configured to totally reflect incident light incident from the first layer at a particular incidence angle due to the inclination angle of the first slope and a refractive index ratio of the first layer and the second layer, the second region is configured to transmit or refract at least some of incident light incident from the first layer at the particular incidence angle due to the inclination angle of the second slope and a refractive index ratio of the first layer and the second layer, and a transparency in the second region is higher than a transparency in the first region only when the counterfeit-preventive optical element is observed from the first layer at the particular incidence angle, characterized in that at least a part of the first region and at least a part of the second region produce a parallax image; and in that when the counterfeit-preventive optical element is observed from two observation points (VpL, VpR) and incident light (PiLa, PiRa) incident at an incidence angle θ 4 is refracted on the interface between air and the first layer at a refractive angle θ 5 giving refracted light (PfLb, PfRb) refractive index N 1 and refractive index N 2 satisfy expressions: when θ > θ 5: θ + θ 5 ≥ arcsin N 2 / N 1 > θ − θ 5; when θ = θ 5: 2 × θ 5 ≥ arcsin N 2 / N 1; when θ < θ 5: θ + θ 5 ≥ arcsin N 2 / N 1 > θ 5 − θ; where θ is the inclination angle of the slope of the relief structure, θ 5 is the refractive angle of light incident at the angle of convergence, N 1 is a refractive index of the first layer, and N 2 is a refractive index of the second layer; and wherein the refractive angle θ 5 is expressed by: θ 5 = arcsin sin θ 8 / 2 / N 1 = arcsin sin θ 4 / N 1 where θ 8 is the angle of convergence, and θ 4 is the incidence angle of the incident light (PiLa, PiRa). a first layer; a second layer having a refractive index different from a refractive index of the first layer; and a third layer partly welded or joined to the first layer, wherein the first layer, the second layer, and the third layer are stacked in this order, a relief structure is provided between the first layer and the second layer, the first layer at least includes a first region and a second region, an inclination angle of a first slope of the relief structure in the first region differs from an inclination angle of a second slope of the relief structure in the second region, the first region is configured to totally reflect incident light incident from the first layer at a particular incidence angle due to the inclination angle of the first slope and a refractive index ratio of the first layer and the second layer, the second region is configured to transmit or refract at least some of incident light incident from the first layer at the particular incidence angle due to the inclination angle of the second slope and a refractive index ratio of the first layer and the second layer, and a transparency in the second region is higher than a transparency in the first region only when the counterfeit-preventive optical element is observed from the first layer at the particular incidence angle, characterized in that at least a part of the first region and at least a part of the second region produce a parallax image; and in that when the counterfeit-preventive optical element is observed from two observation points (VpL, VpR) and incident light (PiLa, PiRa) incident at an incidence angle θ 4 is refracted on the interface between air and the first layer at a refractive angle θ 5 giving refracted light (PfLb, PfRb) refractive index N 1 and refractive index N 2 satisfy expressions: when θ > θ 5: θ + θ 5 ≥ arcsin N 2 / N 1 > θ − θ 5; when θ = θ 5: 2 × θ 5 ≥ arcsin N 2 / N 1; when θ < θ 5: θ + θ 5 ≥ arcsin N 2 / N 1 > θ 5 − θ; when θ > θ 5: θ + θ 5 ≥ arcsin N 2 / N 1 > θ − θ 5; when θ = θ 5: 2 × θ 5 ≥ arcsin N 2 / N 1; when θ < θ 5: θ + θ 5 ≥ arcsin N 2 / N 1 > θ 5 − θ; where θ is the inclination angle of the slope of the relief structure, θ 5 is the refractive angle of light incident at the angle of convergence, N 1 is a refractive index of the first layer, and N 2 is a refractive index of the second layer; and wherein the refractive angle θ 5 is expressed by: θ 5 = arcsin sin θ 8 / 2 / N 1 = arcsin sin θ 4 / N 1 where θ 8 is the angle of convergence, and θ 4 is the incidence angle of the incident light (PiLa, PiRa).