This research set to examine the impacts of collaborative learning (CL), scaffolding instruction, and self-assessment on reading anxiety, reading motivation, and reading comprehension of Iranian EFL learners. Based on Preliminary English Test (PET) results, a sample of 58 students was chosen to represent the study’s sample subject out of a total of 71 participants. Running a convenience sampling technique, two equal groups (the control and experimental) were chosen at random from among them. Afterward, both groups completed pretests to gauge their reading motivation, anxiety, and comprehension. Two groups were then treated with a variety of treatments. Learners in the experimental group got scaffolding instruction, self-assessment, and CL as treatment, whereas the control group received typical instructor-based teaching and assessment. Later, both groups took the post-test for reading anxiety, reading comprehension, and reading motivation after the treatment. According to the one-way ANCOVA analysis, the post-test results for the two groups were different. Based on the data analysis, the experimental group outdid the control group in reading anxiety, reading motivation, and reading comprehension. It was concluded that Iranian EFL learners were able to develop both their reading comprehension and reading motivation while experiencing less reading anxiety thanks to CL, self-assessment, and scaffolding instruction. Finally, the conclusions, implications, limitations, and suggestions for further studies were provided.