Nasalized vowels are syllables with nasal consonant endings. When the nasal consonant ending is weakened, the vowel part takes on a nasal characteristic. Among the three major dialects of Guangdong, only the Min dialect has this characteristic. This characteristic is not easily distinguished by non-native speakers. The documentation of nasalized monophthongs in Eastern Guangdong Min has predominantly relied on transcribers' perception rather than precise data. Most research on this topic remains at the phonetic description level, lacking acoustic analysis. This study conducts an acoustic analysis of the nasalization degree of the vowel /ĩ/ across three age groups (elderly, middle-aged, young) in Eastern Guangdong Min, examining the retention of nasalized vowels /ĩ/ in actual pronunciation and discussing the necessity and feasibility of acoustic measurement for recording nasalized vowels. The findings reveal that the elderly exhibit the highest nasalization degree, with a discernible nasalization trend in non-nasalized vowels based on the data. In contrast, middle-aged and young speakers partially confuse nasalized and non-nasalized vowels. This underscores the importance of enhancing precision in describing nasalized vowels according to actual conditions during dialectal phonetic transcription.