[Solved]-How to draw line from Data label to Marker in Highchart Scatter Plot-Highcharts

You can add another scatter series with and modify it a bit to show connections and dataLabels.

series: [{
      type: 'scatter',
      data: [{
        name: 'First',
        x: 0,
        y: 29.9,
        dataLabels: {
          enabled: false
        }
      }, {
        name: 'Second',
        x: 0.1,
        y: 39.9,
        dataLabels: {
          formatter: function() {
            return 'test label';
          },
          x: 20,
          y: 0
        },
        marker: {
          enabled: false,
          radius: 0
        }
      }],
    },
]

Options chart to set behavior, with enableMouseTracking: false to turn off mouse tracking, lineWidth: 1 to draw line (connections to point) and showInLegend: false for hide series in legend.

  plotOptions: {
    scatter: {
      states: {
        inactive: {
          enabled: false
        }
      },
      dataLabels: {
        enabled: true,
        allowOverlap: true,
        crop: false,
        overflow: 'allow',
        align: 'center',
        verticalAlign: 'bottom',
        useHTML: true,
      },
      lineWidth: 1,
      color: 'red',
      enableMouseTracking: false,
      showInLegend: false
    },
  }

live demo: http://jsfiddle.net/BlackLabel/hpds8f0x/2/