In a moving picture coding apparatus, a first determining section determines whether the parameter is less than or equal to a predetermined threshold and a first measuring section, for each divided blocks, measures time duration while the first determining section is determining that the parameter is less than or equal to the predetermined threshold. After that, a second determining section determines whether the time duration comes up to a predetermined condition. Then, a coding control section forcibly sets intra-coding for a block, if the second measuring section determined that the time duration has come up to the condition.