Two experiments were carried out to clarrify the influence of dietary levels of protein and energy on the egg production characteristics of laying Japanese quail (Couturnix coturnix japonica) in medium temperature period (from Autumn to Spring) and high temperature period (at Summer). In experiment 1, 540 quail of 3 months old were divided into 9 groups and fed 9 designed diets of CP content (%) and ME value (kcal/g) as 16-2.7, 16-3.0, 163.3, 20-2.7, 20-3.0, 20-3.3, 24-2.7, 24-3.0, 24-3.3 from Octorber to March on an average 21.0°C and from July to Septenber on an average 27.7°C. In experiment 2, 9 experimental diets as 18-2.6, 18-3.1, 18-3.6, 24-2.6, 24-3.1, 24-3.6, 30-2.6, 30-3.1, 30-3.6 were fed to 540 quail of 3 months old from March to May on an average 22.0°C and from June to August on an average 29.8°C. Two experiments were conducted repeatedly under 21.4°C from Octorber to March and 29.8°C from June to August in experiment 1, and 22.6°C from April to June and 29.6°C from July to Septenber in experiment 2. A variance analysis and an estimation of response surface for the analysis of data obtained were used. The results were as follow:1) It was shown by the variance analysis that the interactions between and among the temperatures and dietary factors were not significant. It is considered that the above thing shows that the response of egg production by the CP contents and the ME levels in diets is mostly resemble between the medium and the high temperature period in which the ambient temperature was different.2) The egg production rate raised by the step-down in accordance with the level-up of CP content. The maximum rate reached with 24% and 26% of CP in experiment 1 and 2, respectively. In the range of the higher level than 24% and 26%, no changes of the rate by the CP content was brought about. On the other hand, in the range of the above CP content, increasing the level-up of ME from 2.8kcal raised the rate. It is said that from the above response surface the optimum level of CP content and ME value for the rate are 25% and 3.0kcal.3) The effect of CP content on egg weight was significant and the weight increased by the step-down with the level-up of CP. While, the effect of ME level upon egg weight was brought about by the interaction of CP content and ME level; in the range from 18% of CF to 23, the level-up of ME became the cause of weight decrease, and in the range from 23 to 30, caused weight increase.4) It was shown that the feed efficiency in the range from 24% of CF to 30 was higher than the efficiency in 18, and it was made better by the level-up of ME.5) From the above results, the composition of CP and ME in which the highest egg production rate, heavier egg and higher feed efficiency are obtained is said to be 25% and 3.0kcal.