There is no doubt that the implementation of CLIL in Spain changed the current education system. Students need more help as they are facing a new challenge which includes many difficulties for them. For this reason, the main objective of this paper is to justify and evaluate the importance of scaffolding both for input and output phases, in addition to the justification of its importance throughout the entire learning process. With the aim of justifying the use of scaffolding in a CLIL classroom as an essential element for students to achieve the objectives of each educational stage, this work investigates different authors and psycholinguistic theories related to scaffolding; different techniques that teachers can use in each of the CLIL subjects according to the learning objectives; the importance of the use of ICT to motivate students and the need to adapt learning to new paradigms in education. Therefore, in this paper all these topics are evaluated to finally justify and determine that scaffolding is essential in Primary Education because of some reasons such as students’ necessities, motivation factors, academic difficulties, or activities in which they use several skills at the same time, among others.