This article examines the effect of control degree of main clause on finiteness and tense in Persian complement clauses. Landau considers the obligatoty control of main clause verb on the predicate of finite and nonfinite complement clause. The semantic interpretation of predicate of main clause determines the mood and finiteness of the dependent clause using finiteness and tense. Increasing the control intensity of main clause on the occurrence of complementary clause increases the degree of non‌finiteness of complementary clause. The purpose of this article is to examine the effect of finiteness and tense on the occurrence of dependent clause regarding to the degree of control of main clause based on Landau’s Minimalism and Givon’s Functionalism. The data of research has been collected in a library manner and analyzed by a descriptive-analytical method. Results are indicative of gradability of tense and finiteness in complement clauses. By decreasing the control intensity of main clause verb, the occurrence time of complementary clause has less reference to main clause. The mood and finiteness of complement clauses are changed from nonfinite subjunctive mood to finite indicative mood; so finiteness can be defined as a continuum from nonfiniteness to weak, moderate and complete finiteness.