This research examined the idea that children's parent-oriented motivation underlies the benefits of parents' involvement on children's engagement and ultimately achievement in school. Beginning in the fall of 7th grade, 825 American and Chinese children (mean age 12.73 years) reported on their parents' involvement in their learning as well as multiple dimensions of their motivation in school every 6 months until the end of 8th grade. Information on children's self-regulated learning strategies and grades was also obtained. Over time, the more involved parents were in children's learning, the more motivated children were to do well in school for parent-oriented reasons, which contributed to children's enhanced self-regulated learning and thereby grades. Although children's parent-oriented motivation was associ- ated with their controlled and autonomous motivation in school, it uniquely explained the positive effect of parents' involvement on children's grades. There is much evidence to support the idea that parents' in- volvement in children's learning (e.g., discussing children's schoolwork with them and attending parent-teacher conferences) facilitates children's learning and ultimately their achievement (for recent reviews, see Grolnick, Friendly, & Bellas, 2009; Pomerantz & Moorman, 2010). Compared with the support children receive from teachers and peers, the role parents play in children's learning is often considered not only unique but also essential (e.g., Furrer & Skinner, 2003; Grolnick & Ryan, 1992). Given the importance of parents' involvement in children's learning, a major question is that of what underlies its beneficial effect on children's achieve- ment. In response to this question, multiple mechanisms have been proposed (for a review, see Pomerantz, Kim, & Cheung, 2012). Key is that parents' involvement enhances children's achievement through its influence on their motivation (Grolnick, Ryan, & Deci, 1991; Grolnick & Slowiaczeck, 1994). In this vein, children's autonomous motivation and feelings of agency have been found to underlie the effect of parents' involvement on their achievement (e.g., Grolnick et al., 1991; Grolnick & Slowiaczeck, 1994; Hong & Ho, 2005). The current work was guided by the perspective that parents' involvement contributes to children's achievement via their moti- vation. However, it represents a departure from prior work in its focus on the role of motivation that may be experienced by children largely as controlled. Specifically, children's parent- oriented motivation was examined as a mechanism through which parents' involvement facilitates children's achievement during the early adolescent years. The goal was to evaluate the model illus- trated in Figure 1. It was postulated that when parents are involved in children's learning, children become motivated in school for parent-oriented reasons (e.g., to show parents they are responsible and gain parents' approval); such motivation heightens children's engagement, thereby enhancing their achievement. The model was tested in the United States and China to identify its validity in cultures in which the nature of parents' involvement in children's learning differs (e.g., Chao, 1994, 1996; Cheung & Pomerantz, 2011).