Abstract; This study was designed to investigate sources of individual differences in musical skill acquisition. We had 171 undergraduates with little or no piano-playing experience attempt to learn a piece of piano music with the aid of a video-guide, and then, following practice with the guide, attempt to perform the piece from memory. A panel of musicians evaluated the performances based on their melodic and rhythmic accuracy. Participants also completed tests of working memory capacity, fluid intelligence, crystallized intelligence, processing speed, and two tests of music aptitude (the Swedish Music Discrimination Test and the Advanced Measures of Music Audiation). Measures of general intelligence and music aptitude correlated significantly with skill acquisition, but mindset did not. Structural equation modeling revealed that general intelligence, music aptitude, and mindset together accounted for 22.4% of the variance in skill acquisition. However, only general intelligence contributed significantly to the model (β = 0.44, p < .001). The contributions of music aptitude (β = 0.08, p = .39) and mindset (β = −0.06, p = .50) were non-significant after accounting for general intelligence. We also found that openness to experience did not significantly predict skill acquisition or music aptitude. Overall, the results suggest that after accounting for individual differences in general intelligence, music aptitude and mindset do not predict piano skill acquisition in beginners.