The purposes of the current study were 1) to investigate problems in instructing literacy and fluency of reading and writing of Thai L1 young learners, and 2) to investigate needs in instructing literacy and fluency of reading and writing of Thai L1 young learners. There were 2 groups of participants including a group of 15 samples answering a questionnaire and a group of 10 samples taking part in an interview session. The instruments were 1) a questionnaire and 2) a structured interview to study problems in instructing literacy and fluency of reading and writing skills of Thai young learners and 3) a questionnaire and 4) a structured interview to study needs in instructing literacy and fluency of reading and writing skills of Thai young learners. The quantitative data were analyzed using percentages, mean scores, and standard deviation. Meanwhile, the results of the interview were analyzed by a qualitative analysis method. The results of the study show that 1) problems in instructing literacy and fluency of reading and writing skills of Thai L1 young learners are the learners' knowledge in textual language systems in terms of spelling, meaning, and uses in both receptive and productive manners; 2) needs in instructing literacy and fluency of reading and writing skills of Thai L1 young learners rely on finding possible solutions to solve these problems considering the nature of young learners' learning.