diff --git a/plugins/parsers/csv/parser.go b/plugins/parsers/csv/parser.go
index 8e0b8b47..cfa91e4e 100644
--- a/plugins/parsers/csv/parser.go
+++ b/plugins/parsers/csv/parser.go
@@ -17,8 +17,8 @@ type Parser struct {
 	HeaderRowCount    int
 	SkipRows          int
 	SkipColumns       int
-	Delimiter         string
-	Comment           string
+	Delimiter         rune
+	Comment           rune
 	TrimSpace         bool
 	ColumnNames       []string
 	TagColumns        []string
@@ -37,11 +37,11 @@ func (p *Parser) compile(r *bytes.Reader) (*csv.Reader, error) {
 	csvReader := csv.NewReader(r)
 	// ensures that the reader reads records of different lengths without an error
 	csvReader.FieldsPerRecord = -1
-	if p.Delimiter != "" {
-		csvReader.Comma = []rune(p.Delimiter)[0]
+	if p.Delimiter != 0 {
+		csvReader.Comma = p.Delimiter
 	}
-	if p.Comment != "" {
-		csvReader.Comment = []rune(p.Comment)[0]
+	if p.Comment != 0 {
+		csvReader.Comment = p.Comment
 	}
 	return csvReader, nil
 }
diff --git a/plugins/parsers/csv/parser_test.go b/plugins/parsers/csv/parser_test.go
index e3668d3a..b6eef0ed 100644
--- a/plugins/parsers/csv/parser_test.go
+++ b/plugins/parsers/csv/parser_test.go
@@ -106,7 +106,7 @@ func TestQuotedCharacter(t *testing.T) {
 func TestDelimiter(t *testing.T) {
 	p := Parser{
 		HeaderRowCount:    1,
-		Delimiter:         "%",
+		Delimiter:         '%',
 		ColumnNames:       []string{"first", "second", "third"},
 		MeasurementColumn: "third",
 		TimeFunc:          DefaultTime,
@@ -122,7 +122,7 @@ func TestDelimiter(t *testing.T) {
 func TestValueConversion(t *testing.T) {
 	p := Parser{
 		HeaderRowCount: 0,
-		Delimiter:      ",",
+		Delimiter:      ',',
 		ColumnNames:    []string{"first", "second", "third", "fourth"},
 		MetricName:     "test_value",
 		TimeFunc:       DefaultTime,
@@ -152,7 +152,7 @@ func TestValueConversion(t *testing.T) {
 func TestSkipComment(t *testing.T) {
 	p := Parser{
 		HeaderRowCount: 0,
-		Comment:        "#",
+		Comment:        '#',
 		ColumnNames:    []string{"first", "second", "third", "fourth"},
 		MetricName:     "test_value",
 		TimeFunc:       DefaultTime,
diff --git a/plugins/parsers/registry.go b/plugins/parsers/registry.go
index 28ff3026..cb5ba71b 100644
--- a/plugins/parsers/registry.go
+++ b/plugins/parsers/registry.go
@@ -226,20 +226,20 @@ func newCSVParser(metricName string,
 		return nil, fmt.Errorf("there must be a header if `csv_column_names` is not specified")
 	}
 
+	var delimiterRune rune
 	if delimiter != "" {
-		runeStr := []rune(delimiter)
-		if len(runeStr) > 1 {
+		if len(delimiter) > 1 {
 			return nil, fmt.Errorf("csv_delimiter must be a single character, got: %s", delimiter)
 		}
-		delimiter = fmt.Sprintf("%v", runeStr[0])
+		delimiterRune = []rune(delimiter)[0]
 	}
 
+	var commentRune rune
 	if comment != "" {
-		runeStr := []rune(comment)
-		if len(runeStr) > 1 {
+		if len(comment) > 1 {
 			return nil, fmt.Errorf("csv_delimiter must be a single character, got: %s", comment)
 		}
-		comment = fmt.Sprintf("%v", runeStr[0])
+		commentRune = []rune(comment)[0]
 	}
 
 	parser := &csv.Parser{
@@ -247,8 +247,8 @@ func newCSVParser(metricName string,
 		HeaderRowCount:    headerRowCount,
 		SkipRows:          skipRows,
 		SkipColumns:       skipColumns,
-		Delimiter:         delimiter,
-		Comment:           comment,
+		Delimiter:         delimiterRune,
+		Comment:           commentRune,
 		TrimSpace:         trimSpace,
 		ColumnNames:       columnNames,
 		TagColumns:        tagColumns,