This study explores how motivation and incentives impact college students’ volunteer service within civil practices. Utilizing a factor analysis data model, we constructed factor loadings for volunteer service work, rotated the factor matrix, and estimated the correlation coefficients of factors using regression methods. Our “motivation-incentive” analytical model frames this research, alongside proposed hypotheses. Descriptive analysis of the sample confirmed these hypotheses. Results reveal a significant path coefficient of 0.224 (p < 0.001) for engagement on continued volunteering willingness, underscoring engagement’s positive influence. Furthermore, positive emotions in volunteering motivation significantly correlate with engagement and sustained service willingness (coefficients: 0.315, 0.745, 0.269; p < 0.01), serving as a mediator. This study elucidates the mechanisms of influence in volunteer work, offering theoretical guidance for enhancing college students’ participation in civilized practice volunteer services.