The purpose of this study is to classify the types of the construction ‘-ulkka po-’ based on the syntactic characteristics and to reveal the meaning of each type. The functions and meaning of ‘-ulkka po-’ appears to be different depending on the syntactic environment. Therefore the types of constructions are classified by syntactic environment. And meanings of each types are provided. ‘-ulkka po-’ constructions with connective endings bare [speculation], [apprehension], or [expectation] meaning. It is also noteworthy that the meaning of [apprehension] is stronger than the meaning of [expectation]. ‘-ulkka po-’ constructions with final endings signify [speculation], [intention], [warning], or [rhetoric question] meaning. The [expectation], [apprehension], [intention], and [rhetoric question] meaning were derived from [speculation] meaning, while [threatening] was derived from [intention]. However, the construction of [speculation] is a quatative construction rather than auxiliary verb construction.