The tridimensional sexual desire proposal (i.e., dyadic to partner, dyadic to attractive other and solitary) has been empirically supported. However, solitary sexual desire and its relationship to other dimensions of sexual functioning has received less attention. Hence, we examined the capacity of solitary sexual desire to explain the subjective orgasm experience (Study 1) and sexual arousal (Study 2) in the context of solitary masturbation. Study 1, composed of 2406 heterosexual adults (M age = 39.72, SD = 11.81), assessed for solitary sexual desire, dyadic sexual desire, and the intensity of the subjective orgasm experience obtained through solitary masturbation, along with other associated parameters. Study 2, consisting of 41 heterosexual young people (M age = 22.49, SD = 3.17), evaluated the genital response (penile circumference/vaginal pulse amplitude) and subjective arousal to sexually explicit films related to solitary masturbation. In both men and women, solitary sexual desire accounted for a significant percentage of the subjective orgasm experience obtained through solitary masturbation. In addition, in women, the propensity for sexual arousal was explained by solitary sexual desire. It is concluded that solitary sexual desire -as opposed to dyadic- is important to explain sexual arousal and orgasm in the solitary masturbation context. These results highlight the importance of addressing sexual desire in the solitary context, given its implications with other dimensions of sexual functioning.